Installed sub in my 2011 BOSE Impala. Pac audio makes aoem gm 1416 to integrate the amp and everything. Worked great until i noticed lately passenger rear speakers not working. Use to work fine. After swapping amp and another pac module same problem persists. When module is unplugged and factory set is in place all speakers work fine. As soon as module hooked up the passenger side rear speakers go out. All other speakers work. Cannot understand what is going. Any help?