Is it possible to play sound in mono? I'm in a workplace that only allows one headphone in. This makes some music pretty awful, only having one channel. I'd like to mix my audio into one channel, but this seems to be a bit more difficult than you would expect. I don't want to buy a paid app, and I'm playing music from my Google Music library, so alternate players aren't an option.

Is there any way to do this digitally? I don't want to have to buy an adapter and have it sticking out of my phone, risking my headphone jack, just to play mono.

I'm on a Droid X2 running CM9. I know some of the manufacturer ROMs had mono options, but it's not in stock Android or CM9.
There's a  setting under  accessibility options for mono audio.  I  haven't tried it yet,  but it may be what you want.