Xtl2500 random out of range

I have several hundred of these radios and randomly for no reason at all one will begin to flash out of range and will no work on our trunking system. This has happened to dozens of them.

In service mode they test right on freqnecy for Recv and transmit on freq and on power programmed.



Motorola can not give me any ideas as far as a firmware problem. I have to send them to the depot and they simply factory reset the radio and I dump the codeplug back in and its fine. Is there a way I can factory reset the radio or a way to empty the code plug so it has no data and rebuild it?? Im at a lose



Thanks