Dear Maintainer,
I had to revert back the following packages:

[DOWNGRADE] alsa-ucm-conf:amd64 1.2.15-1 -> 1.2.14-1
[DOWNGRADE] alsa-utils:amd64 1.2.15-1 -> 1.2.14-1
[DOWNGRADE] libasound2-data:amd64 1.2.15-2 -> 1.2.14-2
[DOWNGRADE] libasound2-plugins:amd64 1.2.12-2+b4 -> 1.2.12-2+b1
[DOWNGRADE] libasound2t64:amd64 1.2.15-2 -> 1.2.14-2
[DOWNGRADE] libatopology2t64:amd64 1.2.15-2 -> 1.2.14-2

to have back my audio sinks and mic. With the new version of the pakages, in fact, pipewire/wireplumber only offers the "Dummy output" and no mic at all.
At the same time this does not seem to be a pure alsa issue since invoking:

speaker-test -Dplughw:CARD=sofsoundwire,DEV=2 -c 2 -t sine

I hear the expected sound from my speakers, even with the 1.2.15 version of the libraries.

Notice that "aplay -l" and "aplay -L" produce the exact same result with the 1.2.14 and 1.2.15 alsa libraries.
I am attaching the output of pw-dump command executed with alsa libs 1.2.14 and 1.2.15, in case they could help understanding where the problem stands.

Final note: I have an ArrowLake notebook (Intel(R) Core(TM) Ultra 7 265H - Dell Pro Max 16 Premium MA16250).

Is there anything I can do to help debugging this issue?

Sincerely
  G.

Dear maintainers,
it turn out this is a duplicate of:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1123857
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1124077
Indeed, the only package that creates the problem is alsa-ucm-conf (the
other alsa packages I was mentioning in my original message can be safely
upgraded as they do not break pipewire).

Looking at the two related bugs above, it turns out alsa-ucm-conf has been
already patched upstream, so it is just a matter of installing the upstream
files (see also: https://github.com/alsa-project/alsa-ucm-conf/issues/663 )
or waiting debian maintainers to package the new version of asa-ucm-conf.

At this point this bug can be closed.

Thanks