that's freaky, I came on hear to ask the same exact question! as I'm also using audicity... and it won't let me do it in mp3 either...

I was using dB power amp, aparently I only had a 30 day free trail, because it used to work, now it tells me that my trial has expired... so, yeah, you have to pay for it now...

but the thing that you suggested PRSplaya, I downloaded it, it took like a minute, and converted it, it took like 30 seconds... now I'm going to go post my new song in the listening post. so, the software you recommended is just what I needed. thanks!