Quoted from delt31:I think amp might be blown. Could be what happened here:
https://pinside.com/pinball/forum/topic/tech-help-pleaselost-bass-soundspeaker-on-ripleys-bion
Here's the question - can I swap my MET pro sound board with ST pro to see if it's the amp?
Yes, The amp is part of the sound board. If your swap boards and get sound, that will tell you it is a bad sound board.