What little I could decipher from him is the A channel output only works with A\/B combined, or mono. In straight stereo only the B channel output works. The A output is the one that does not work in stereo mode so that's the "blown channel", or more likely inoperative output? Meaning the amp section is unaffected?\n\nI'm using the A output so it is not in stereo. "B flows into A". I'm making a bunch of assumptions, but to me it sounds like it's bridged, no?\n\nYou can only tell by the wiring. If using A 1+\/1- you are using CH A. If using A 2+\/2- you are using CH B. If using A 1+\/2+ you are in bridge mode, but the Mode selector should also be set to Bridge then, not mono.