Interesting results so far – the fact that the MCL2AV AUX socket connection allowed control was useful, but I too don’t understand why there was no sound. I thought that pins 1 and 4 always output the sound from MCL2AV. My gear is put away at the moment so I think it will be next week before I am able to try anything similar (with a known working MCL2AV), but until then I will be following with interest!
I am also confused as to why the sound is not comming through as it is from the BM5500 that also output sound on pin 1 and 4. I think I will have to focus on fixing the instabilities in my MCL2AV to be sure of the results.