Cadence amplifier not working properly?

I have a cadence z1200 4 channel amplifier not working properly. Not sure whats wrong with it, its acting like its not getting a good current from the rcas but they are brand new and have only been used with 1 other amp for a few months. Im running at 1 ohm bridged and when I turn the volume up and down on the head unit the bass stays the same unless i go way down and my subs start making weird noises none of the buttons or knobs work either, when the beat stops and the singer is talking the subwoofers make very strange noises. This was a free amplifier and the original owner said it may not work. Any help??