This was literally the first thing that I did to our brand new trailer the day we got it home. Outside speakers did not work and inside was halfway wired up. Pulled the head unit out and saw the rats nest that they had cobbled up and just shook my head
So i just cut it all loose and rewired it the correct way. If there is one thing I have gathered from this forum and others, no matter what brand rv you get, they all have issues and basically if you want something done right just do it yourself