Volume level problem with aftermarket headunit
So I had a REC nav system with the amplified factory stereo. I just installed a Pioneer AVH-X5500BHS using a PAC RP4-CH11 adapter. I'm getting some static noise across the radio when the volume is all the way down. I can only turn the radio up to about 6 on the volume setting (max is 50 i believe) before its too loud. I checked everything and it looks like its hooked up right but it seems to be outputting way too loud.
2005 WK Limited 5.7l QD II - Stock for now.
1991 YJ SOA, Dana 44 rear, 4.56, locked front and rear, wagoner leaf stretch, 35s