Audio redo

The sound quality of the stereo speakers, freed of their cases, was disappointing.  I examined adding baffling behind them, but the bulk created space issues.

ALSO - one of the speakers popped off the case, despite being secured with epoxy.  Came to discover the epoxy rather easily came off the plastic everywhere.  So I removed it from the Pi and audio amp standoffs and replaced it with cyanoacrylate (Super Glue).  Seems to be holding.

I had this old mono speaker module from a discarded laptop. I knew I'd use it one day. It's actually bass-reflex design, with a port! Really sounds nice. So I rewired the audio amp to bridge the stereo output to mono, removed the unnecessary on-off switch, and replaced the audio-in plug with a right-angle version from some dead headphones.  That way it won't stick-out too much when plugged into the Pi.  I debated rewiring the Pi to send it internal, but external allows the port to be used for A/V also (it has a composite out, I think).