Some time ago I reported I had an intermitant fault when the young lady on sat nav (doris), would leave her mike switched on after giving instructions. As you can imagine, very annoying, losing radio/CD.MP3 etc. This could only be fixed by switching off the radio, until she spoke again of course...although not every time.
It was recommended by this forum the NIM was at fault. (navigation Interface Modual)
as still under warranty, I got the MOCO to replace.
Now, although the problem has now gone away.....I'm not 100% certain it was the NIM at fault.
The MOCO engineer in his wisdom on hearing it was an intermitant fault looked for AND found dodgy wiring in the harness.
This is a Roadglide 2011 CVO.
found couple of wires inside under the fairing which were bare, not not broken.
He repaired these wires, installed some foam on sharp edges around the radio, still replaced the NIM after taking off the fairing anyway.
so. moral of story, if outside of warranty and its intermitant same problem, then check for broken wires around the radio, as I understand that NIMs are fairly expensive.