Sound problem with kernels above 5.9

That’s alright, one last thing tho’ just for curiosity sake. Have a look at these two outputs for your system.

systemctl --user status pipewire.service
examine the systemd pipewire service status, it should all be loaded and good
pactl info
This one gives info about the pulse-pipewire interface, including the sink/sources
and
aplay -l
which lists your alsa hardware layer devices. See this reddit for an explanation : https://www.reddit.com/r/archlinux/comments/kjj8gs/kde_plasma_pipewire/
but I think you have the same problem or a similar problem.

My output:

[spongebob@krabby-patty ~]$ systemctl --user status pipewire.service
● pipewire.service - Multimedia Service
     Loaded: loaded (/usr/lib/systemd/user/pipewire.service; disabled; vendor preset: enabled)
     Active: active (running) since Wed 2021-06-23 20:11:08 BST; 3h 27min ago
TriggeredBy: ● pipewire.socket
   Main PID: 1342 (pipewire)
      Tasks: 2 (limit: 19095)
     Memory: 17.5M
        CPU: 8.930s
     CGroup: /user.slice/user-1000.slice/user@1000.service/session.slice/pipewire.service
             └─1342 /usr/bin/pipewire

Jun 23 20:11:08 krabby-patty systemd[1236]: Started Multimedia Service.

[spongebob@krabby-patty ~]$ pactl info
Server String: /run/user/1000/pulse/native
Library Protocol Version: 34
Server Protocol Version: 35
Is Local: yes
Client Index: 53
Tile Size: 65472
User Name: spongebob
Host Name: krabby-patty
Server Name: PulseAudio (on PipeWire 0.3.30)
Server Version: 14.0.0
Default Sample Specification: float32le 2ch 48000Hz
Default Channel Map: front-left,front-right
Default Sink: alsa_output.pci-0000_0e_00.4.analog-stereo
Default Source: alsa_output.pci-0000_0e_00.4.analog-stereo.monitor
Cookie: c34c:9d19
[spongebob@krabby-patty ~]$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: HDMI [HDA ATI HDMI], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: HDMI [HDA ATI HDMI], device 7: HDMI 1 [HDMI 1]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: HDMI [HDA ATI HDMI], device 8: HDMI 2 [HDMI 2]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: HDMI [HDA ATI HDMI], device 9: HDMI 3 [HDMI 3]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: HDMI [HDA ATI HDMI], device 10: HDMI 4 [HDMI 4]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: Generic [HD-Audio Generic], device 0: ALC887-VD Analog [ALC887-VD Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
[spongebob@krabby-patty ~]$ lsmod | grep snd_seq
snd_seq_dummy          16384  0
snd_seq                86016  7 snd_seq_dummy
snd_seq_device         16384  1 snd_seq
snd_timer              40960  3 snd_seq,snd_hrtimer,snd_pcm
snd                   114688  18 snd_hda_codec_generic,snd_seq,snd_seq_device,snd_hda_codec_hdmi,snd_hwdep,snd_hda_intel,snd_hda_codec,snd_hda_codec_realtek,snd_timer,snd_compress,snd_soc_core,snd_pcm

That last comment on the reddit thread:

I found that it works if I modprobe snd_seq and restart the service, but this isn’t really a fix since it worked yesterday perfectly fine.

might work for you if there is a kernel module loading problem that is preventing your hardware sound device becoming available. You can check if the snd_seq module is loaded with lsmod | grep snd_seq
and restart the pipewire service: systemctl --user restart pipewire.service