[HumbleAg]

Ok, now I'm officially in over my head. I understand your explanation, but the wire that isn't there is the one on Pin G, so if that is the issue, the XM would likely be causing the pop. The onstar should still be ok (but I didn't test it when I had everything hooked up). It does make sense to me that the XM could be popping because a signal isn't getting transmitted through.

BTW, I didn't get an XM adapter (I don't subscribe now) and I also haven't renewed Onstar (although I know the system should still work).

Easy enough to test, I'll jumper the wires like Peripheral does and see what happens.

I've read some other forums where people say the Metra adapter does the same thing, so I'm thinking maybe there is just an issue with the adapter design. Nothing yet from the ebay guy I bought the adapter from (no big surprise there).

Any issues with the Peripheral adapters? Can you adjust the chime volume, or is the volume ok by default?

Thanks again for the help.