I have a 2009 Ultra Classic that has the stock factory Harmon-Kardon radio receiver unit. Recently it has started to cut out on the volume but it still shows on the display that it is on and playing. The only way to get the sound back on is to turn the unit off and back on and then it will come back on for a few miles then cut out again. This is very annoying and the Harley dealership says nothing can be found wrong. Anyone else ever heard of or had this problem?