Well, I recorded the stream with SoundTap and there was a lot of background/white noise in the recording. I tried messing around with the Noise Removal feature in Audacity, but that didn't seem to fix it. I didn't have time to run headphone > M10, so I had little to compare it with. Oh well, live and learn. I'll have to practice a little before the next show.
Thanks, again, for all the advice.