Just hooked up amp & subs, have a strage nosie now

[Corvette Don]

I used HIGH level inputs (no rca cables) and "briged" both speakers (it sounds better) and now when I either turn the car off or just the radio off (car running) the subs make a high pitched loud "waaaaaaaa" noise that lasts a good 2 seconds. It does not matter what the volume is at on the radio either. Any idea how to fix this??

[58REX]

it could be one of two things. it could be in the ground of the amp. also i have had that happen if amp is not set to be bridged. some amps will not allow this to happen.

[scott_fx]

check the grounds