I just noticed this on the 8800 I bought yesterday - I inadvertently tapped the bottom of the phone on my desk and it caused the device to reset (as if the battery was removed and reinserted). Same thing happened when I set it down in the cupholder of my car. I experimented with it and the same thing happened tapping the top. Anyone else notice this problem? (That never happened with my 8700)

Only had this happen one time and it was a fall to a granite counter top and it did a reset. I think it pushed the battery away from the contacts for a split second. If yours is doing it often, there may be something loose inside and needs to be replaced.