More than likely that is what it is. Been having issues with mine lately but once the outside temp warms up it will go away. Sometimes if you unplug the wiring harness and plug it back in the problem is solved.
The volume control and a couple of preset buttons are now not lit up. How hard is it to change the bulb behind the those controls and what bulb do you use?
Just make sure before you get off any major roads to fuel up. Some of the places we have been it's tough enough to get fuel with a 33 ft TT let alone a 5ver with something behind that.