Dark pixel glitch with multiple response

[cww3]

Hi, thanks for your reply. Changing the s parameter didn't fix it -- it's really a very strange error and I'm not sure what it was. However, I fixed the problem by including a blank item with a 1-second duration, and that seemed to "clear" the screen so that the dots didn't appear.

[Trevor Newell]

Hm - great to hear that you were able to find a solution to the problem.
Thank you for posting what you discovered about the bug.