# Builder

**URL:** https://discourse.psychopy.org/c/builder/5.md?page=1

[Latest](https://discourse.psychopy.org/latest.md) · [Categories](https://discourse.psychopy.org/categories.md) · [Tags](https://discourse.psychopy.org/tags.md)

**Page:** 2

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## [Experiment won't open- Unhandled internal error](https://discourse.psychopy.org/t/experiment-wont-open-unhandled-internal-error/47677)

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**Author:** [@Rozhin\_Nemati\_Mood](https://discourse.psychopy.org/u/Rozhin_Nemati_Mood)\
**Replies:** 2\
**Last updated:** [August 19, 2026, 9:36am UTC](https://discourse.psychopy.org/t/experiment-wont-open-unhandled-internal-error/47677 "2026-08-19T09:36:33Z")

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Hi, I encountered this error seemingly out of nowhere and can’t figure out what the issue is. I’m super new to Psychopy and programming in general so any help would be super appreciated. Traceback (most recent call last…

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## [UnboundLocalError: local variable ‘video’ referenced before assignment (MovieStim initialized too late from Builder?)](https://discourse.psychopy.org/t/unboundlocalerror-local-variable-video-referenced-before-assignment-moviestim-initialized-too-late-from-builder/47657)

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**Author:** [@monicathieu](https://discourse.psychopy.org/u/monicathieu)\
**Replies:** 2\
**Last updated:** [August 18, 2026, 4:53pm UTC](https://discourse.psychopy.org/t/unboundlocalerror-local-variable-video-referenced-before-assignment-moviestim-initialized-too-late-from-builder/47657 "2026-08-18T16:53:04Z")

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If this template helps then use it. If not then just delete and start from scratch. OS: Mac OS 2026.5.1 PsychoPy version: Studio 2026.2.1 Standard Standalone Installation? (y/n) No, PsychoPy Studio Do you want it to …

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## [Crash in pilot mode](https://discourse.psychopy.org/t/crash-in-pilot-mode/47681)

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**Author:** [@JensBoelte](https://discourse.psychopy.org/u/JensBoelte)\
**Replies:** 2\
**Last updated:** [August 17, 2026, 12:16pm UTC](https://discourse.psychopy.org/t/crash-in-pilot-mode/47681 "2026-08-17T12:16:48Z")

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OS macOS Tahoe 26.61. PsychoPy version 2026.1.3 Standard Standalone Installation? (y/n) y Do you want it to also run online? (y/n) y What are you trying to achieve?: I use the following code to counterbalance group…

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## [Keypress not recognised in Builder experiments ran in desktop - MacOS](https://discourse.psychopy.org/t/keypress-not-recognised-in-builder-experiments-ran-in-desktop-macos/47656)

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**Author:** [@eanisimova](https://discourse.psychopy.org/u/eanisimova)\
**Replies:** 1\
**Last updated:** [August 13, 2026, 11:18am UTC](https://discourse.psychopy.org/t/keypress-not-recognised-in-builder-experiments-ran-in-desktop-macos/47656 "2026-08-13T11:18:31Z")

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OS (e.g. Win10): Mac OS 15.5 PsychoPy version (e.g. 2024.2.4 Py 3.8): 2026.1.3 (although I have tried downloading and running both previous and newer versions posted on GitHub and the issue persists). Standard Standalo…

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## [PsychoPy Studio 2026.2.1: Pilot in Browser opens blank page with ERR\_CONNECTION\_REFUSED and WebSocket handshake failure on macOS](https://discourse.psychopy.org/t/psychopy-studio-2026-2-1-pilot-in-browser-opens-blank-page-with-err-connection-refused-and-websocket-handshake-failure-on-macos/47605)

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**Author:** [@thenicholasruiz](https://discourse.psychopy.org/u/thenicholasruiz)\
**Replies:** 1\
**Last updated:** [August 12, 2026, 2:21pm UTC](https://discourse.psychopy.org/t/psychopy-studio-2026-2-1-pilot-in-browser-opens-blank-page-with-err-connection-refused-and-websocket-handshake-failure-on-macos/47605 "2026-08-12T14:21:37Z")

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I am unable to pilot an experiment in a browser from PsychoPy Studio 2026.2.1 on macOS. When I click Pilot Experiment in Browser, a browser window opens but remains blank. PsychoPy Studio then displays an error dialog t…

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## [Core.rush(enable = TRUE) error causes Builder experiment to crash in RUN mode](https://discourse.psychopy.org/t/core-rush-enable-true-error-causes-builder-experiment-to-crash-in-run-mode/47641)

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**Author:** [@eanisimova](https://discourse.psychopy.org/u/eanisimova)\
**Replies:** 6\
**Last updated:** [August 12, 2026, 2:06pm UTC](https://discourse.psychopy.org/t/core-rush-enable-true-error-causes-builder-experiment-to-crash-in-run-mode/47641 "2026-08-12T14:06:17Z")

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OS : Mac OS 15.5 PsychoPy version : Initially built and tried in Psychopy 2025.2.1, then re-saved and tried again in 2026.1.3. Standard Standalone Installation? (y/n): y Do you want it to also run online? (y/n): y W…

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## [Installed PsychoPy Studio but psychopy python lib not installed/found?](https://discourse.psychopy.org/t/installed-psychopy-studio-but-psychopy-python-lib-not-installed-found/47588)

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**Author:** [@monicathieu](https://discourse.psychopy.org/u/monicathieu)\
**Replies:** 5\
**Last updated:** [August 11, 2026, 8:45pm UTC](https://discourse.psychopy.org/t/installed-psychopy-studio-but-psychopy-python-lib-not-installed-found/47588 "2026-08-11T20:45:54Z")

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OS: Mac OS 2026.5.1 PsychoPy version: Studio 2026.1.3 Standard Standalone Installation? (y/n) No, PsychoPy Studio Do you want it to also run online? (y/n) No What are you trying to achieve?: I am developing a new l…

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## [Adding multiple additional resources?](https://discourse.psychopy.org/t/adding-multiple-additional-resources/47618)

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**Author:** [@thenicholasruiz](https://discourse.psychopy.org/u/thenicholasruiz)\
**Replies:** 1\
**Last updated:** [August 7, 2026, 9:57am UTC](https://discourse.psychopy.org/t/adding-multiple-additional-resources/47618 "2026-08-07T09:57:22Z")

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when adding additional resources through the builder for an experiment intended to run on pavlovia, is there a simpler way to add hundreds of files? i have hundreds of stimulus images in separate subfolders, but when add…

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## [Builder creates movie.stop() which crashes program](https://discourse.psychopy.org/t/builder-creates-movie-stop-which-crashes-program/47626)

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**Author:** [@samEccleston](https://discourse.psychopy.org/u/samEccleston)\
**Replies:** 3\
**Last updated:** [August 6, 2026, 3:06pm UTC](https://discourse.psychopy.org/t/builder-creates-movie-stop-which-crashes-program/47626 "2026-08-06T15:06:19Z")

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OS: macOS Monterey 12.7.6 PsychoPy version: 2022.2.5 Standard Standalone Installation? (y/n): Yes Do you want it to also run online? (y/n): No What are you trying to achieve?: I am trying to code a block fMRI design…

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## [Issue with syncing with Pavlovia after the update](https://discourse.psychopy.org/t/issue-with-syncing-with-pavlovia-after-the-update/46309)

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**Author:** [@kumarvar](https://discourse.psychopy.org/u/kumarvar)\
**Replies:** 9\
**Last updated:** [August 5, 2026, 6:05pm UTC](https://discourse.psychopy.org/t/issue-with-syncing-with-pavlovia-after-the-update/46309 "2026-08-05T18:05:21Z")

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OS (e.g. Win10): MacOS PsychoPy version (e.g. 2024.2.4 Py 3.8): 2025.1.1 Link to the most relevant existing thread you have found: Pavlovia maintenance on 27 Dec 2025 The issue: I am trying to make changes to my expe…

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## [Adaptive Staircase jumps to maximum intensity and never decreases (PsychoPy 2025.1.1)](https://discourse.psychopy.org/t/adaptive-staircase-jumps-to-maximum-intensity-and-never-decreases-psychopy-2025-1-1/47613)

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**Author:** [@Saravana\_Priyan\_T](https://discourse.psychopy.org/u/Saravana_Priyan_T)\
**Replies:** 0\
**Last updated:** [August 3, 2026, 3:50am UTC](https://discourse.psychopy.org/t/adaptive-staircase-jumps-to-maximum-intensity-and-never-decreases-psychopy-2025-1-1/47613 "2026-08-03T03:50:02Z")

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OS (e.g. Win10): Win 10 pro PsychoPy version (e.g. 2024.2.4 Py 3.8): 2025.1.1 Standard Standalone Installation? (y/n) Yes Do you want it to also run online? (y/n) No Hi everyone, I am encountering an issue with the…

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## [Experiment suddenly doesn't work](https://discourse.psychopy.org/t/experiment-suddenly-doesnt-work/47600)

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**Author:** [@sharonting](https://discourse.psychopy.org/u/sharonting)\
**Replies:** 0\
**Last updated:** [July 30, 2026, 12:17am UTC](https://discourse.psychopy.org/t/experiment-suddenly-doesnt-work/47600 "2026-07-30T00:17:41Z")

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OS (e.g. Win10): Win10 PsychoPy version (e.g. 2024.2.4 Py 3.8): Tried re-installing 2026.1.3, and also tried on 2026.2.1 Standard Standalone Installation? (y/n) If not then what?: y Do you want it to also run online?…

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## [Incorrect Reaction Time Values](https://discourse.psychopy.org/t/incorrect-reaction-time-values/47571)

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**Author:** [@Eylul1](https://discourse.psychopy.org/u/Eylul1)\
**Replies:** 4\
**Last updated:** [July 27, 2026, 3:59pm UTC](https://discourse.psychopy.org/t/incorrect-reaction-time-values/47571 "2026-07-27T15:59:13Z")

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OS: Windows 11 PsychoPy version : PsychoPy Standalone 2026.1.3 Hello, I have a recognition memory experiment created in Builder. The experiment runs correctly and saves data correctly, but the keyboard RT values are…

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## [UnboundLocalError: local variable 'watching' referenced before assignment](https://discourse.psychopy.org/t/unboundlocalerror-local-variable-watching-referenced-before-assignment/47563)

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**Author:** [@Dzhaner\_Emilov\_Stefa](https://discourse.psychopy.org/u/Dzhaner_Emilov_Stefa)\
**Replies:** 2\
**Last updated:** [July 27, 2026, 1:57pm UTC](https://discourse.psychopy.org/t/unboundlocalerror-local-variable-watching-referenced-before-assignment/47563 "2026-07-27T13:57:48Z")

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If this template helps then use it. If not then just delete and start from scratch. OS (e.g. Win10): PsychoPy version (e.g. 2026.1.3): Standard Standalone Installation? (y/n) yes Do you want it to also run online? (y…

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## [Generating Code to Shuffle Outcomes Lists](https://discourse.psychopy.org/t/generating-code-to-shuffle-outcomes-lists/47556)

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**Author:** [@Charlotte\_Gagnon](https://discourse.psychopy.org/u/Charlotte_Gagnon)\
**Replies:** 1\
**Last updated:** [July 24, 2026, 11:15am UTC](https://discourse.psychopy.org/t/generating-code-to-shuffle-outcomes-lists/47556 "2026-07-24T11:15:28Z")

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PsychoPy version 2026.1.3 Hi there! I am building a modified Iowa Gambling Task and am trying to write a code to shuffle between 4 premade lists of outcomes, so every participant gets a different set of outcomes every e…

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## [Counterbalancing Central vs. Peripheral Face Presentation in PsychoPy (EEG Experiment)](https://discourse.psychopy.org/t/counterbalancing-central-vs-peripheral-face-presentation-in-psychopy-eeg-experiment/47436)

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**Author:** [@Sannihit](https://discourse.psychopy.org/u/Sannihit)\
**Replies:** 8\
**Last updated:** [July 23, 2026, 11:09pm UTC](https://discourse.psychopy.org/t/counterbalancing-central-vs-peripheral-face-presentation-in-psychopy-eeg-experiment/47436 "2026-07-23T23:09:02Z")

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OS (e.g. Win10). PsychoPy version (e.g. 2025.1.1 Py 3.8). Hi everyone, I am designing an EEG experiment in PsychoPy and would appreciate some guidance on implementing counterbalancing efficiently. I have added the ima…

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## [Feature Request: Built-in Macro Recorder for Repetitive Builder Tasks](https://discourse.psychopy.org/t/feature-request-built-in-macro-recorder-for-repetitive-builder-tasks/47549)

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**Author:** [@jason533](https://discourse.psychopy.org/u/jason533)\
**Replies:** 1\
**Last updated:** [July 23, 2026, 4:17pm UTC](https://discourse.psychopy.org/t/feature-request-built-in-macro-recorder-for-repetitive-builder-tasks/47549 "2026-07-23T16:17:08Z")

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Hi everyone, I often find myself repeating the same sequence of actions when creating or editing experiments in PsychoPy Builder. A built-in macro recorder could allow users to record repetitive actions and replay them …

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## [Multiple mouse click responses](https://discourse.psychopy.org/t/multiple-mouse-click-responses/47546)

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**Author:** [@shreyak](https://discourse.psychopy.org/u/shreyak)\
**Replies:** 2\
**Last updated:** [July 23, 2026, 1:37pm UTC](https://discourse.psychopy.org/t/multiple-mouse-click-responses/47546 "2026-07-23T13:37:58Z")

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If this template helps then use it. If not then just delete and start from scratch. OS (e.g. Win10): macOS Tahoe 26.5.2 PsychoPy version (e.g. 2024.2.4 Py 3.8): 2026.1.3 Standard Standalone Installation? (y/n) If not…

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## [Setting the audio driver](https://discourse.psychopy.org/t/setting-the-audio-driver/47540)

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**Author:** [@marac](https://discourse.psychopy.org/u/marac)\
**Replies:** 2\
**Last updated:** [July 23, 2026, 9:36am UTC](https://discourse.psychopy.org/t/setting-the-audio-driver/47540 "2026-07-23T09:36:29Z")

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Hi guys, I want to minimize the delay of my auditory stimuli while working on fMRI tasks. Do you think setting the PTB to 3 is sufficient and necessary? from psychopy import prefs prefs.hardware\[‘audioLib’\] = \[‘PTB’\] …

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## [Form Component 'free text'](https://discourse.psychopy.org/t/form-component-free-text/40125)

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**Author:** [@LelBartha](https://discourse.psychopy.org/u/LelBartha)\
**Replies:** 5\
**Last updated:** [July 22, 2026, 5:54pm UTC](https://discourse.psychopy.org/t/form-component-free-text/40125 "2026-07-22T17:54:52Z")

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I’m using PsychoPy version 2023.2.3 on windows 10. I’m using the form component with the following .csv file: Testing2.csv (144 Bytes) My problem is that the “Text Here…” text is not in the box where they need to enter…

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## [Help me with connecting PsychoPy with Tobii Pro Lab](https://discourse.psychopy.org/t/help-me-with-connecting-psychopy-with-tobii-pro-lab/47493)

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**Author:** [@r.y](https://discourse.psychopy.org/u/r.y)\
**Replies:** 1\
**Last updated:** [July 21, 2026, 6:45pm UTC](https://discourse.psychopy.org/t/help-me-with-connecting-psychopy-with-tobii-pro-lab/47493 "2026-07-21T18:45:26Z")

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If this template helps then use it. If not then just delete and start from scratch. OS (e.g. Win10): Win10 Pro PsychoPy version (e.g. 2024.2.4): 2024.2.4 Standard Standalone Installation? (y/n) :Yes, I guess. Do you …

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## [fMRI considerations](https://discourse.psychopy.org/t/fmri-considerations/47528)

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**Author:** [@marac](https://discourse.psychopy.org/u/marac)\
**Replies:** 0\
**Last updated:** [July 20, 2026, 9:20am UTC](https://discourse.psychopy.org/t/fmri-considerations/47528 "2026-07-20T09:20:05Z")

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Hi everyone, Did anyone use the BIDS Plugin to handle neuroimaging data? Do you find it relatable for fMRI?

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## [Eyetracker not found in experiment settings](https://discourse.psychopy.org/t/eyetracker-not-found-in-experiment-settings/47503)

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**Author:** [@meiyoucoding](https://discourse.psychopy.org/u/meiyoucoding)\
**Replies:** 0\
**Last updated:** [July 16, 2026, 7:15pm UTC](https://discourse.psychopy.org/t/eyetracker-not-found-in-experiment-settings/47503 "2026-07-16T19:15:57Z")

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Hi everybody, I’m trying to connect the Gazepoint eyetracker in the latest version of PsychoPy Studio Beta. I have installed the plugin into the builder, yet the eyetracker does not show up under eyetracking in experimen…

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## [Hypersync Experiment Building protocol](https://discourse.psychopy.org/t/hypersync-experiment-building-protocol/47491)

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**Author:** [@Saumya](https://discourse.psychopy.org/u/Saumya)\
**Replies:** 2\
**Last updated:** [July 16, 2026, 9:52am UTC](https://discourse.psychopy.org/t/hypersync-experiment-building-protocol/47491 "2026-07-16T09:52:48Z")

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We are building an experiment for hyperscanning study on Psychopy. We want to build a cooperative task where participants are supposed to perform a task simultaneously by giving a response together. The task will look s…

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## [Considerations for fMRI](https://discourse.psychopy.org/t/considerations-for-fmri/47473)

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**Author:** [@marac](https://discourse.psychopy.org/u/marac)\
**Replies:** 5\
**Last updated:** [July 14, 2026, 9:40am UTC](https://discourse.psychopy.org/t/considerations-for-fmri/47473 "2026-07-14T09:40:24Z")

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Hi! I am currently designing some fMRI experiments using PsychoPy, and I am wondering what factors are essential to consider, particularly regarding timings. Since I am working with auditory stimuli, I need precision and…

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## [Allow camera access](https://discourse.psychopy.org/t/allow-camera-access/47452)

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**Author:** [@BelleLyons](https://discourse.psychopy.org/u/BelleLyons)\
**Replies:** 1\
**Last updated:** [July 13, 2026, 11:03am UTC](https://discourse.psychopy.org/t/allow-camera-access/47452 "2026-07-13T11:03:31Z")

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How can I get PsychoPy to allow camera access on Mac?

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## [Touch input unreliable in PsychoPy (pyglet) on Windows 11 touch monitor](https://discourse.psychopy.org/t/touch-input-unreliable-in-psychopy-pyglet-on-windows-11-touch-monitor/47450)

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**Author:** [@heegoo\_kim](https://discourse.psychopy.org/u/heegoo_kim)\
**Replies:** 2\
**Last updated:** [July 13, 2026, 5:44am UTC](https://discourse.psychopy.org/t/touch-input-unreliable-in-psychopy-pyglet-on-windows-11-touch-monitor/47450 "2026-07-13T05:44:47Z")

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\*\*OS\*\*: Windows 11 Pro \*\*PsychoPy version\*\*: tested on 2024.1.5 and 2026.1.3 (issue persists on both) \*\*Standard Standalone\*\*: Yes I’m running a Corsi block-tapping working memory task (Builder, code component using …

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## [Randomizing outcome lists](https://discourse.psychopy.org/t/randomizing-outcome-lists/47446)

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**Author:** [@Charlotte\_Gagnon](https://discourse.psychopy.org/u/Charlotte_Gagnon)\
**Replies:** 3\
**Last updated:** [July 9, 2026, 9:02pm UTC](https://discourse.psychopy.org/t/randomizing-outcome-lists/47446 "2026-07-09T21:02:51Z")

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PsychoPy version : 2026.1.3 I am running a modified Iowa Gambling Task (IGT) and have different outcome lists associated with 2 card choices. I would like to randomize the outcomes (how much money they win or lose when …

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## [PsychoPy 2026.1.3 audio error: "No speaker device found with index 'None'" on macOS](https://discourse.psychopy.org/t/psychopy-2026-1-3-audio-error-no-speaker-device-found-with-index-none-on-macos/47300)

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**Author:** [@emanuela\_phi](https://discourse.psychopy.org/u/emanuela_phi)\
**Replies:** 2\
**Last updated:** [July 2, 2026, 6:39pm UTC](https://discourse.psychopy.org/t/psychopy-2026-1-3-audio-error-no-speaker-device-found-with-index-none-on-macos/47300 "2026-07-02T18:39:26Z")

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Hi everyone, I’m new to PsychoPy so please excuse me if this is a easy problem to solve. I’m trying to build a very simple experiment on macOS.The task is straightforward: participants press the space bar, a second rou…

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## [Over-riding default monitor selection](https://discourse.psychopy.org/t/over-riding-default-monitor-selection/47418)

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**Author:** [@stanley1O1](https://discourse.psychopy.org/u/stanley1O1)\
**Replies:** 0\
**Last updated:** [July 1, 2026, 5:19pm UTC](https://discourse.psychopy.org/t/over-riding-default-monitor-selection/47418 "2026-07-01T17:19:24Z")

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This is just a picky QOL problem I am having. I would like to have it so that when I build a new experiment, the default monitor selection is not “testMonitor” and is instead the monitor I created in the monitor centre.…

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