Amp Problems

Hey, I just got an amp from my dad and i hooked it up but the bass hits arent constant. Instead of a base hits sounding like booooooooooom! The base hit sounds like boooo, buh, buh, buh, buh, buh, buh, buh, til the base ends and it keeps on going like that on all of the base hits. Whats wrong?
It's a sherwood. 180 watts x 2 channels. It has a mono/stereo switch, one set of rca inputs, battery + and - remote, and the power regulator. (Just so you guys know what it looks like)

What do you have hooked up to the amp? What kind of speakers? and how are they hooked up?

I connected the battery +, -, and the remote to where they are supposed to go. I connected the rca's where they go as well and i connected two 300 watt bazookas to the two channels. I also have another subwoofer connected to the + of one bazooka and to the - of the other.

I believe the third subwoofer you have connected to the + of one and the - of the other is connected in what is called a "Bridged mode" (If I am mistaked somebody correct me). In order to do this your amp needs to be a "Bridgeable" amp. This may be causing your problem. I am a work now but I will check my references when I get home and let you know. In the mean time if you'd like just disconnect this third sub and see if you still have the problem.