i had the same thing in my bonerville...moved the system over to other cars and havent had the same results....only differences was wiring harness and where it was grounded.
2007 GXP: Magnaflow Cat-back, F/R STB, MSP Poly Motor Mount, Kicker 15" Solobaric, ZR1000, Pioneer HU, Donrome Locks, Custom FWI, HP tune in progress