I encountered something similar on my N900 while using Panucci (0.3.17) a few days ago. The podcast I was listening to kept on playing, but the phone responded to nothing else. Headphoned wouldn't stop the playback on disconnecting headphones, but it switched to speakers and back to headphones properly when connecting / disconnecting the headphones. Even long press on power button to power off wouldn't work, I had to pull the battery. I don't have sshd running so I couldn't get in to see what's going on.

I didn't associate it with Panucci then, and it might well have been something completely different. Never seen anything like this before though.