I would say that the best thing to do, for anyone who is having such problems, is to do a complete uninstall, including the TV database, reinstall and configure everything and test again.
It is quite possibly a corrupted database or something similar. Since no-one on the team can reproduce the problem, it is difficult for us to determine whether there actually is a bug.
At least if it happens on a clean install with a new database, we will know that this is something that should be looked into.
Mark