I now have a picture of my installation if anybody's interested to see it. Yeah, it's blurry. We'll try again later.

Also, my friend with the digital camera could be described as "fidgety". She was blasting away at the EMPEG while I was trying to drive. One problem comes up if you just changed the volume with the knob and then immediately want to change the track. The left/right buttons are interpreted as changing the volume. You either have to hit the up button to cancel the volume-change mode, or you have to wait. For my fidgety friend, this proved annoying.

Feature request: If you change the volume with the knob, parse the left/right button clicks in their top-level context (track skip, fast forward, rewind, etc.) rather than as volume controls.