Communications Support Forums

I have a bit of an odd problem. We recently updated our XPR 4550s from R01.09.00 to R01.12.15 (codeplug 11.00.10 -> 13.02.01). Now we have complaints that every few hours, about 5 or 6, the volume on the unit will just disappear. The display will light up with a call but nothing can be heard. The radios are on a single analog channel with no scan. The only solution is to power off the unit and back on, then it returns to normal. Has anyone seen this before?