uaudio(4) seems to be broken in NetBSD-9.1

[Brian Buhrow <buhrow%nfbcal.org@localhost>]

	hello.  I just filed kern/pr 55856, which documents the failure of
uaudio(4) devices under NetBSD-9.1.  These are devices which work fine
under FreeBSD-12 and previous versions of NetBSD, including NetBSD-3, 4 and
5.  However, I'm sure I've used these devices on NetBSD-versions as early
as NetBSD-2 and, I think, even earlier.  I suspect this is a regression
from the new audio subsystem that went into NetBSD-9.  In any case, if
anyone has thoughts on how to go about resolving this, I'd be very
interested.

-thanks
-Brian