Pioneer aftermarket radio and XM

[MN2Sailor]

Guys, need your help here. I replaced the factory radio with a Pioneer AVH-5700BHS , and it sounds great. Although i used a GM3A-RSTX interface the OnStar sounds horrible. Excessively distorted. i cant even connect to Bluetooth without it sounding bad. I replaced the interface but i still have the same issue. I replaced the radio back and it works fine. Anyways, has anyone had this problem? How did you fix it? Also second question, using factory XM radio on the Pioneer, the connection is different, anyone run into an interface that will work?