This is a 1% problem.
If it's any consolation, I can't reproduce it either, but I also haven't spent much time examining the issue, so maybe I just haven't tried hard enough.
Work with a statistically significant number of teams and you'll run across it.
We'd see it more if more teams used the IO board.
My experience with it has only been a single team at NJ in triage for more serious issues, so not much time was spent on this one problem. A work around was good enough.
I believe the problem was narrowed down to the Cypress Board (although I didn't test the USB cable connecting it to the Classmate).
Classmates were swapped out and it followed the Cypress board.
Cypress board plugged directly into the right Classmate USB port.
It could be produced by sleep and by repeatedly plugging and unplugging the USB connector.
It only happened on the Enhanced IO for the one I saw.
I did not have time to try a different cable or IO board from Spare Parts.
Cypress tech. support was consulted by phone by the team before the Regional, so take my comment about Cypress knowing about it with a grain of salt. The mentor is quite experienced in LabVIEW real-time processing however (and expressed the typical complaints about some of the low-level non real-time calls employed
).