Car is an 07 Mazda 3 with the standard 6 disc changer.
Here's what I did:
Stock radio with Navone 4 channel LOC, Scosche MA03 and MA03R harnesses
4 channel amp for stock speakers (for now) and 2 channel bridged to sub.
So I've been doing the install all day, and I thought I was done. When I...