Ok, here it is:
I simply purge the offending (residue, incompatible) packages:
root@mx:/home/KL# apt purge pipewire* libspa-0.2*
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Note, selecting 'pipewire-media-session-alsa' for glob 'pipewire*'
Note, selecting 'pipewire-media-session' for glob 'pipewire*'
Note, selecting 'pipewire-pulse' for glob 'pipewire*'
Note, selecting 'pipewire-audio-client-libraries' for glob 'pipewire*'
Note, selecting 'pipewire' for glob 'pipewire*'
Note, selecting 'pipewire-media-session-pulseaudio' for glob 'pipewire*'
Note, selecting 'pipewire-tests' for glob 'pipewire*'
Note, selecting 'pipewire-v4l2' for glob 'pipewire*'
Note, selecting 'pipewire-libcamera' for glob 'pipewire*'
Note, selecting 'pipewire-setup-mx' for glob 'pipewire*'
Note, selecting 'pipewire-jack' for glob 'pipewire*'
Note, selecting 'pipewire-media-session-jack' for glob 'pipewire*'
Note, selecting 'pipewire-audio' for glob 'pipewire*'
Note, selecting 'pipewire-bin' for glob 'pipewire*'
Note, selecting 'pipewire-doc' for glob 'pipewire*'
Note, selecting 'pipewire-alsa' for glob 'pipewire*'
Note, selecting 'libspa-0.2-dev' for glob 'libspa-0.2*'
Note, selecting 'libspa-0.2-libcamera' for glob 'libspa-0.2*'
Note, selecting 'libspa-0.2-jack' for glob 'libspa-0.2*'
Note, selecting 'libspa-0.2-bluetooth' for glob 'libspa-0.2*'
Note, selecting 'libspa-0.2-modules' for glob 'libspa-0.2*'
Package 'pipewire-pulse' is not installed, so not removed
Package 'pipewire-media-session' is not installed, so not removed
Package 'pipewire-audio' is not installed, so not removed
Package 'pipewire-doc' is not installed, so not removed
Package 'pipewire-alsa' is not installed, so not removed
Package 'pipewire-audio-client-libraries' is not installed, so not removed
Package 'pipewire-jack' is not installed, so not removed
Package 'pipewire-libcamera' is not installed, so not removed
Package 'pipewire-media-session-pulseaudio' is not installed, so not removed
Package 'pipewire-tests' is not installed, so not removed
Package 'pipewire-v4l2' is not installed, so not removed
Package 'pipewire-media-session-alsa' is not installed, so not removed
Package 'pipewire-media-session-jack' is not installed, so not removed
Package 'pipewire-setup-mx' is not installed, so not removed
Package 'libspa-0.2-bluetooth' is not installed, so not removed
Package 'libspa-0.2-dev' is not installed, so not removed
Package 'libspa-0.2-jack' is not installed, so not removed
Package 'libspa-0.2-libcamera' is not installed, so not removed
The following packages were automatically installed and are no longer required:
libconfig++9v5 libffado2 libopenfec1 libpipewire-0.3-common libroc0.3 libxml++2.6-2v5
Use 'sudo apt autoremove' to remove them.
The following packages will be REMOVED:
libpipewire-0.3-0* libpipewire-0.3-modules* libspa-0.2-modules* pipewire* pipewire-bin*
0 upgraded, 0 newly installed, 5 to remove and 0 not upgraded.
After this operation, 10.7 MB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 323574 files and directories currently installed.)
Removing pipewire:amd64 (1.2.7-1~mx23+1) ...
Removing pipewire-bin (1.2.7-1~mx23+1) ...
Removing libpipewire-0.3-modules:amd64 (1.2.7-1~mx23+1) ...
Removing libpipewire-0.3-0:amd64 (1.2.7-1~mx23+1) ...
Removing libspa-0.2-modules:amd64 (1.2.7-1~mx23+1) ...
Processing triggers for man-db (2.11.2-2) ...
Processing triggers for libc-bin (2.36-9+deb12u9) ...
(Reading database ... 323231 files and directories currently installed.)
Purging configuration files for pipewire-bin (1.2.7-1~mx23+1) ...
Purging configuration files for pipewire:amd64 (1.2.7-1~mx23+1) ...
Now I install the pw-setup package:
root@mx:/home/KL# apt install pipewire-setup-mx
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following additional packages will be installed:
gstreamer1.0-pipewire libcamera0.0.3 liblc3-0 libldacbt-abr2 liblttng-ust-common1
liblttng-ust-ctl5 liblttng-ust1 liblua5.4-0 libpipewire-0.3-0 libpipewire-0.3-modules
libspa-0.2-bluetooth libspa-0.2-jack libspa-0.2-libcamera libspa-0.2-modules
libwireplumber-0.4-0 pipewire pipewire-alsa pipewire-bin pipewire-jack pipewire-pulse
pipewire-v4l2 wireplumber
Suggested packages:
libcamera-ipa wireplumber-doc
Recommended packages:
rtkit
The following packages will be REMOVED:
pulseaudio
The following NEW packages will be installed:
gstreamer1.0-pipewire libcamera0.0.3 liblc3-0 libldacbt-abr2 liblttng-ust-common1
liblttng-ust-ctl5 liblttng-ust1 liblua5.4-0 libpipewire-0.3-0 libpipewire-0.3-modules
libspa-0.2-bluetooth libspa-0.2-jack libspa-0.2-libcamera libspa-0.2-modules
libwireplumber-0.4-0 pipewire pipewire-alsa pipewire-bin pipewire-jack pipewire-pulse
pipewire-setup-mx pipewire-v4l2 wireplumber
0 upgraded, 23 newly installed, 1 to remove and 0 not upgraded.
Need to get 4,630 kB of archives.
After this operation, 12.6 MB of additional disk space will be used.
Do you want to continue? [Y/n]
I’m brave, because nothing to loose in that VM.
So choosed to install, then reboot, and
it works…