motion tracker changes Vizard timing

[jelly]

Dear Jeff,

I will try to post some code later this evening, the script is so large by now, it really is difficult to tell what is causing it. So I will need to try and create a simpler version.

In principle, I think it could be related to frequency or sampling. I've had a colleague who has told me that she had sounds in her script (like me) and they did not play at exactly the same time from one execution to the next. Another one had a countdown timer clock that was sometimes skipping the display of seconds. And another who had a beep sound that played three times at the end of a trial. There was supposed to be a 1s gap between each beep but sometimes the gaps were audibly uneven and the timer on screen was a bit slow. While for them this was not crucial, the timing of the sounds in my experiment is! All of us were/are using the Polhemus motion tracker.

I will follow this up later with a less complex code version that hopefully still illustrates the problem!