Ok, this may be a stupid question, but there is NO actual sub for the Bose systems right? I just completed my AVIC-D1 install this weekend, and my speakers sound like crap. When I turn it up about 3/4, the sound gets all cracked and distorted. Not that the stock speakers ever sounded that great, but at least there was some thump without any distortion. All that was installed was the HU, PAC-SWI-PS, and Scosche FAI-3 interface adapter. I tried playing around with the gains on the interface adapter, but that didn't do much. Is that only needed when adding after market amp or subs? Anyone have any ideas before I tear into the dash again?

 

What it sounds like is the speaker outputs of the AVIC are overdriving the FAI OR the Bose amp.

I have no experience with that particular adapter, but we wouldn've probably used the Peripheral SVEN4, and run the RCA outs of the Pioneer into it, not the speaker level outs.