Duration stops working with dual screens

Hi everyone,

I have a multiplayer experiment where a visual stimulus is output to two separate screens (one for each participant). When I run the task from the builder where the stimulus is drawn to a single screen, the task runs fine; however, whenever I add the bits of code to have the stimulus drawn to both screens (see below), the routine does not end when it’s supposed to…Instead, the stimulus remains on both screens indefinitely.

win = visual.Window(
    size=[1680, 1050], fullscr=True, screen=0, 
    winType='pyglet', allowGUI=False, allowStencil=False,
    monitor='testMonitor', color=[255,255,255], colorSpace='rgb',
    blendMode='avg', useFBO=True, 
    units='height')

win1 = visual.Window( 
    size=[1680, 1050], fullscr=True, screen=1, 
    winType='pyglet', allowGUI=False, allowStencil=False,
    monitor='testMonitor', color=[255,255,255], colorSpace='rgb',
    blendMode='avg', useFBO=True, 
    units='height')
.
.
.
fixation_cross.draw(win)
fixation_cross.draw(win1)
.
.
.
win.flip()
win1.flip()

Any idea what might be going on? Huge thanks for your help!!

OS: macOS 10.15.4
PsychoPy version: 2021.1.4

Update: I suspect it might have something to do with using a variable for the stimulus duration. I originally had a numerical value for the duration, which works fine, but when try to swap it out for a variable referencing a duration in my conditions file, it no longer works with dual monitors (though still works on a single monitor). Is anyone able to replicate this??