[LV_H2]

I agree, it sounds like a ground problem.

Unfortunately, the adapter comes with a Y harness that simply splits the XM connector for hookup to the XM tuner and the iPod Adapter. No actual ground wire for the adapter.

There is, however, an AUX input (RCA jacks) on the ipod adapter, and there are two "hot power" wires from the harness for connection to an AUX device. I taped these wires off with electrical tape upon install. Maybe these are the problem.

I will be calling the manufacturer tech support to ask them for assistance.

Thanks for the input.