Test your new EVO LTE for this DEFECT!
At work I would stand up and lean over my desk which inadvertently pressed my phone into the desk in this same spot. It vibrated and I took it out and had no messages... I thought maybe I just was making a mistake and ignored it for a couple days until it happened again, same situation, which got me thinking... so I leaned up against my desk again and it happened again. I took the phone out and pressed on it with my thumb and it vibrated. A couple more presses and it got stuck vibrating for 3 hours (seriously), even after the phone shut down due to loss of power, since it could still draw a bit from the battery.
Hold the phone face down and press with a little bit of firm pressure all around the shiny cover (where the board is). My hotspot was above the camera or LED, someone else reported it right below the camera.
If the phone doesn't vibrate, you're good. Sprint will give you a lot of shit if you are outside the 14 days and try to take it back with this problem, so make sure you check it early, maybe even before they activate it. If you're outside the 14 days I wouldn't recommend testing it because you might create the problem that otherwise wasn't there.