Looks like this thread is about a year old but wondering if anyone has tried ANR bose, david clarks, or sennheisers on UAL airbus dual plug setup? I recently tried plugging my Sennheiser hmec 26 (that I use on the 737) and my headset didn't recognize that it was plugged in... ie no mic power). I tried running through different switch options on my headset but on this quick check it didn't seem compatible. I wonder if UAL wired the mic plug with no mic voltage or if this was just a fluke? thx