pkg/56587: netbsd microphone recording regression in firefox91

[nia%pkgsrc.org@localhost]

>Number:         56587
>Category:       pkg
>Synopsis:       netbsd microphone recording regression in firefox91
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Dec 28 15:20:00 +0000 2021
>Originator:     nia
>Release:        n/a
>Organization:
The NetBSD Foundation
>Environment:
NetBSD amnesia 9.99.93 NetBSD 9.99.93 (GENERIC) #2: Mon Dec 27 21:44:48 UTC 2021  nia%procyon.is@localhost:/home/nia/obj2/sys/arch/amd64/compile/GENERIC amd64
>Description:
There is some kind of regression affecting microphone recording in
recent Firefox releases. Samples are returned, but it's noisy and
has basically gone to shit.

Observations:

- Silence is being inserted between samples. It looks like there is some
  disagreement about the audio parameters somewhere.
- As far as I can tell from the cubeb test suite, there is no
  regression, so the problem is not obviously with the underlying
  audio library but something else is happening elsewhere.
- Firefox recently added a new API for measuring input latency, they
  also added a NULL implementation of this for NetBSD. Possibly the
  problem, or not.

I will investigate further until I get too frustrated.
>How-To-Repeat:
I'm using this test page:

https://webaudiodemos.appspot.com/AudioRecorder/index.html

It seems to monitor for samples correctly? Very strange.
>Fix:
downgrade firefox, cry