Pyglet Exception Error : raise GLException(msg) b'stack underflow'

Psychopy 3.9, pyglet 1.5.16, openGL 4.6, NVIDIA GEFORCE GTX 1660 drivers on Windows 11 Pro, 64 bit

Hi everyone,

When trying to run apertures:

aperture = visual.Aperture(myWin,size=1, pos=centerPoint,anchor=None, ori=0, nVert=120, shape=‘circle’,
inverted=False, units=None, name=None, autoLog=None)

I get the following error:

File “C:\Users\SarvestaniM\Anaconda3\envs\pyschopy3_9\lib\site-packages\pyglet\gl\lib.py”, line 107, in errcheck
raise GLException(msg)
pyglet.gl.lib.GLException: b’stack underflow’

Any help greatly appreciated.
MS