head unit, 87 Audi 5000cs

Hi i just bought a JVC KD-HDR1 HD Radio/CD/MP3 Player and i also bought a PAC OEM-2 Universal Interface since my car has the factory amp and 10 speakers. i hooked it up putting the OEM2 between the headunit and the wiring harness so its inline hooked all the wires up like it told me and plugged it in . im only getting sound from the rear passenger speaker and i have to turn the radio up pretty high to do that. i really don't feel like running all new speaker wire since the audi is built like a tank its a pain in the butt. any info would be great. oh almost forgot its an 1987 Audi 5000cs turbo sedan

did you hook up the remote turn on wire?2003 Chevy Avalanche,Eclipse CD7000,Morel Elate 5,Adire Extremis,Alpine PDX-4.150, 15" TC-3000, 2 Alpine PDX-1.1000, 470Amp HO Alt.