I originally posted this in general touring forum, my mistake.
Ok, I've had numerous trouble codes appear, all were U codes. I've managed to clear all except RAD U0186, which is "loss communication with amp 2" code. When I clear this code, I here a pop with static, almost like a ground short, and the trouble code re-appears. Even with the head unit off, when I turn on key, I hear this static pop. Could this be a ground not contacting? Amp in saddlebag is the one setting off code. Does anyone know where this is grounded? Anyone have this trouble?
2014 FLHRTCU with the Boom amps/speakers in front under fairing and in back in saddlebag.

 

Not sure where they might ground a stock rushnore amp. Have you pulled the seat to see if it's ground at the battery?

You could also pull the fairing a d just travel the ground from the amp to where its ground.