Please be aware that as of Friday 2021-09-17 afternoon, the projector is not working properly. I’ve contacted VPixx and will update this thread as the situation progresses.
Note that VPixx is supposed to come next Monday for installing and testing our new screen, so I highly doubt the issue will persist beyond that, if not resolved sooner.
The symptom was the sudden loss of brightness and red and green (everything was dark and blue). Self tests of the projector fail and could indicate faulty memory or a power issue. While the projector is detected again and looks ok after unplugging and restarting it, it may be wiser to postpone bookings for visual studies.
I think the issue is solved. It should be fine to use the projector again.
One thing to remember for future troubleshooting: if the projector is not seen by the computer, it needs to be power-cycled to properly reset, i.e. turning off the power switch on the projector (or the power bar), not simply turning it off with the remote.
I have removed the StarTech computer switch that we used a while back to switch between Stim and Realtime computers (we now only have 1). The 2nd monitor, USB cables to the projector and controller, and audio were all going through that switch. We already had bypassed it for proper projector DVI timing, but it now looks like it was causing issues with the USB connection to the projector as well. So it is now fully removed and all cables go directly to the Realtime computer. The disadvantage is that if a study brings their laptop, they might forget to plug something back.
The issue occurred once again after removing the switch. Only once in over a month though. The temporary solution is to turn off and on both the projector and controller (their physical switches, not just with the remote). However if I am present, please come get me first as I have some quick steps to do to troubleshoot further.
[Notes to self: 2021-10-13
VPutil:
s, this should print the list of devices connected.
rr, this should print … If it did not select the “…” (correct device), run devsel #
tr, this should print some serial number information
sr, this should print a bunch of numbers.]
The issue was not observed for a long time after the controller box was replaced when we got the eye tracker. So seems related to USB. Happened again 2024-09, after changing USB cables because of stim computer USB port issues.