Peva at Bose suggested I post this. He is sending it up to the engineers for further investigation.
I plugged in my new PAS/B1 system directly into my Kurzweil PC2 for a test drive. Beautiful, even sound. Love it.
Tried the remote while playing a fairly delicate piano patch and got what sounded a lot like a dirty pot. (volume control) primarily on the channels and a bit on the master. Called Bose and they sent a new power unit the next day. Best service anywhere, anytime!
Replaced the power unit, remote and cord. Ran the PC2 demo "Fandango" and the stepped sound was gone. I thought the problem was solved. Ran the piano demo (Flaxen Hair) and the stepped sound was back. Put the original power unit back and the same results. I was testing the PAS originally with a piano score I was working on which was similar inlevel to the PC2 piano demo.
Conclusion: A lighter, more delicate sound will produce a stepped or zippered effect when increasing the volume on the remote, especially on the channel control. (Sort of like a bad edit of a MIDI volume message.)
My guess is that the PAS software does some kind of attenuation of the signal to evaluate the level (but I know squat about that kind of stuff - so I am guessing). If the level is strong, no problem, but a weaker level will (or should) produce the "offending" sound.
This should not be much of a problem unless you want to change levels in performance, and then, only if you are at the critical weaker signal level.
Anyone with a PC2 or a light sounding patch or instrument may want to verify this. Again, it is not enough to warrant a return of the power unit (I wish I knew that before Bose went to the trouble and expense). But hopefully, it is something that can be addressed in a future software update.
As always, your comments are most welcome.