MTX amp playing loud distortion

i got a used mtx 2150x amp and when i hooked it up, and tested it, it gave off some loud distortion sound from the sub it was hooked up too. I just see a blurr from the sub, when i fiddle with the bass boost and gains the loud distortion will stop. Actually when i put all the gains and boost to minimum it will stop. I had a similar problem with a kicker amp before and i fixed that problem myself all it was was a tiny surface mount fuse that was blown so i just modified it and replaced it with a regular 1 Amp slow blow fuse. Tested and problem solved with the kicker am that is. Now with the mtx amp, i took it appart and examined it for the same sort of blown fuse at the rca inputs and no signs of a fuse anywhere. I know for sure this is the same problem as the kicker amp but this mtx amp is made differently i guess anyone happen to know how to fix this problem. i know its not my wiring cause i tested in my moms car and she already has an amp i just replaced it with this one and i figured its has a problem and put back my moms old amp and her car is fine now. Help will be greatly appreciated.

IT sounds like one of the op amps on the inputs is toasted, or a feedback loop opened up and one of the stages in the EQ is running open-loop. Take it to a tech and have them check it out, or send it back to MTX. They've always been very good to me with repairs. -daveThis is not a sig. This is a duck. Quack.

they dont want distortion in SPL either. distortion blows woofers, especially at the levels in which they are played in spl comp. to the untrained ear it may sound like distortion, its just that most if not all competitors only have the subs connected, no interior speakers. 1990 Honda Civic HB:

Clarion DXZ545MP H.U.

2- 6.5" Power Acoustik interiors

Diamond Audio 600.1 amp

Diamond Audio 15" M6MKII

Pyramid PB881X 4 CH. Amp