I was trying to help my friend troubleshoot his problem with the speakers. He had his system "professionally" installed and the problem is that when we plugged an ipod in the front USB, the main speakers worked and sounded great, but the Zone 2 speakers (outside installed in ceiling of covered patio) were real fuzzy, almost like you were tuned into a weak FM station. When we switched the source to "FM Radio", the Zone 2 speakers sounded great. We tried switching USB cables but that did not work? Any help is appreciated.