Audio driver work seems to be coming to a head. After several phone conversations with the vendor all signs are pointing to a hardware problem. Possibly noise on a control line. More tests needed to verify.
Bus ride home took forever for reasons unknown. Lots of traffic through Greenfield so a good guess would be some sort of badness in the Squirrel Hill Tunnel or further along the Parkway East.
Guitar lessons continued. Mostly a review of previous techniques but with more challenging chords. Need to find more time to practice.