I have had my EVO since last Friday. I love this thing. However, there seems I have had 2 instances where my phone spontaneously reboots if I have doing GPS turn by turn directions and talking on the phone at the same time while using a bluetooth headset. I play with very popular apps I downloaded from Market; and I am pretty good about not leaving them running in the background. So, I'm thinking theres a very specific scenario that causes the phone to reboot. I doubt there a hardware defect; as it only happens with the above scenario. I am curious if there are other people who push their phones to do simultaneous hardware features at the same time and cause it to reboot. I guess its possible that there may be a 3rd party app that's silently running in the background which might be the cause; however, no matter what, an app shouldnt have the ability to crash the entire OS.