Our first actions were to open it up, re-seat and verify all the cable connectors between boards, and clean the surface of the touch keyboard to rule out anything mechanical. However, we actually figured out what might be going on through research and talking to other people in the synth community. Because this information was pretty hard to track down, we’re posting it here for anyone else who is wondering about it.

 

Apparently this is a known issue that various people have reported, and apparently the recommendation offered by Buchla is to wait for 30 seconds after powering it on before touching it. The circuitry that encodes the feedback received by the keyboard must calibrate itself when the synth is first turned on.  Whatever amount of feedback it is receiving during these initial moments are “tared” from future readings, so if a key is being touched then, it will be effectively be turned off (or almost turned off) for the rest of the playing session. If metal areas other than the keys are touched when it is turned on, any key can be the one to not work.

 

Whenever we waited before touching the keys, we had no problems with any of them, and almost always would if we touched it right after it turned on, so our observations corroborated this theory. However, I can’t promise it will always work perfectly in every environment because the Easel’s design is very, very sensitive to static electricity and electromagnetic interference in the environment from other nearby electrical/electronic devices,  wiring in the building, fluorescent light fixtures, etc. While it was on the work table, we noticed that changing the angle of an adjustable desk lamp about 5 feet away from it could cause it to make a noise.