SynchronEyes 7 - Red Crosses through students?

[TheydonBois]

Suddenly one of the Teacher PCs is showing red crosses through all the students after a few minutes (as though they had all logged off at the same time) before refreshing itself a few minutes later and showing the students once.

Anyone else had this happen, and know a solution?

I have already unistalled and re-installed, and it does the same thing.

Thanks in Advance.

[TheydonBois]

Its running on XP SP3 if that makes a difference. The Students all point to the Teacher PC via name, rather than IP address. No settings have changed.