Blown channel on bg radia bgx-a2 sybwoofer amp

My theater uses four bgx-s12b subwoofers that each use twelve 4" opposing speakers. One of the bgx-a2 amps two channels died "unrepairable" and the amps are rare with BG Radia out of business. Unfortunately the amp contains the circuits that balance the output of the speakers (which peak at 110 Hz when powered by a normal amp). I cannot find a used BGx amp. Solution ideas? 

Sure, you want a plate amp with built in DSP such as this one:

You will still need to configure it. If that makes you uncomfortable, get a regular plate amp without the DSP and get something with room correction upstream.
The word was used by Abell audio of Columbus. They only went as far as to look to the current "BG Radia," a warehouse now. I have put want ads out and will add one to hifishark. Thanks. 
Did you ever resolve you problem? I have 1x bgx-a2 and 2x bgx-s12b subwoofers, and the amp is playing up and *may* need a replacement.

In case there's someone who knows about these things - it started by making a recurrent hum, and so I turned it off for a week or so. Now, when I power it up, it just switches itself off again. If anyone has any suggestions on a fix I'd be very grateful to hear them.