Yesterday, I pulled up the Source menu on my player and saw that there's a "Microphone" source listed. I don't think I'd ever seen it before, so I selected it, even though I don't have anything hooked up to my player's mic jack. It appeared to switch sources, but the player menu went blank, and the only way to switch back was to switch with my remote.

So, what's that all about? Was it always there and I just never noticed it, or is there some reason it suddenly appeared? Can I actually use the mic jack as an input source for, say, my cell phone? I remember that it's a mono connection, and that the sampling rate isn't very high, but it could still be useful if it actually worked.

This is on player 3.0alpha11, BTW.