I have this same problem. It happens to me once a month. If you take the faceplace off, there is a reset button under it. Use a pen or paperclip and press the reset button. You will lose your radio presets and audio settings (bass, treble, loud, etc.), but the bluetooth devices remain.
I have two of these stereos. One in my truck and one in my car. I have never had an issue with the one in my car, so I am thinking there is a defect with the one in my truck. I'm just too lazy to dig out the receipt and take it back to exchange it.
I am having this same problem and I have done everything in the troubleshoot section of the manual including replacing my radio fuse, checking for connection with the black (ground) wire, and checking for connection on the red and yellow wires, but nothing is working. I even tried the solution mentioned above about pressing the reset button and absolutely NOTHING is working. Are there any other things out there to try?