Batboard

I have (3) XPR6550 portable radios all that are running in digital mode. Everything is working fine on the radios except there is no tx modulation on all 3. They are running ver 1.6 firmware. The tx audio does not work on the side connector with a new speaker mic either. Does anyone know if this is a common repair with these radios, or if there is a simple fix such as updating the firmware?????

Check that Analog/Digital Mic AGC is checked. If it is not, check in the "Accessories" section of CPS that the Mic Gains are set to something reasonable (Default is around -5dB). I would update the firmware as there have been voice quality improvements since v1.6.
Out of about 150 portables, I've had one 6550 that had no TX audio; good output just no audio. Sent it back for repair.