The save_src and restore_src sound great to me. The only warning is that all the button codes I've tried for tuner always take it to FM, never back to AM even if that's what you were listening to. It's always struck me as odd, because the empeg integrates AM and FM so well in every other way. I've never tried having the irtranslate go through the menu structure, because I didn't want it to not work if I was in the menus when a phone call came in. I've never tried your nextsource virtual button code though. I'm away from my empeg collection at the moment, so I can't try it now.

My initial plan was (pseduo ir-translate)

extmuteon.T = aux.S
extmuteon.M = aux

extmuteoff.N = player
extmuteoff.S = tuner

But I never got this to work at all, even with the AM/FM limitations.

I'll certainly set up a test bench when I get home to work on this some more, I'd love to get it perfected.

Matthew