Today when i was cleaning out my truck and vaccuming the carpet i moved my subwoofer out of my truck....just disconnected the speaker wires and then moved the amp out of the way. When i put it all back together in has this real low (tone) hum in it and when you turn it off it pops real loud and the woofer moves...i thought my amp was messed up so i changed to another amp i have (perfect working condition) and it didn't hum for about 5 minutes but started huming a little quieter....i checked all my grounds...hooked and unhooked them....RCA's are not crossing and are on different side of the truck...what's wrong?? bad alt?? or bad RCA's?? Help my please i hate not having my bass.

 

Disconnect signal, if it still happens then you got something shorted or not grounded right.

Hook up a portable device, like an ipod, using head phone to RCA adapters. Still got noise? it's downstream of the amp.

Wiggle some wires. Maybe speaker wire has frayed, or some copper elements are causing a short near either terminal set?

Voice coil itself may be shorting. Replace sub.