I had almost the exact same problem, though I wasn’t using the builder, instead I was hard coding the program (on Windows 10). I was able to fix the issue but that’s only because of the hardware in my machine. Basically Psychopy wasn’t working well with my computer’s integrated graphics card. Luckily for me my computer had a separate NVIDIA card for gaming. Once I configured my computer to use that card specifically to run Python graphics, and not the integrated card, the problem was solved. If your computer is using an integrated graphics card that could be the issue.
Here is the link to my topic:
https://discourse.psychopy.org/t/win-flip-lags-after-long-latency/12718/2?u=non_human_entity