On both T400 and x200 running libreboot the EC portion of firmware would load and be default alsa device. This was corrected and is no longer visible in system.

acpi tables are complicated, I know they can be de-compiled and re-compiled. Could be custom setups that may yield more minimal setups. However, I have not experimented with custom setups yet.

**** List of PLAYBACK Hardware Devices ****
card 0: Intel [HDA Intel], device 0: CX20561 Analog [CX20561 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 1: CX20561 Digital [CX20561 Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

Now in alsamixer i see a EC audio device hw29. I imagine this is part of a kernel driver? Something to do with the Kernel and the EC firmware. Firefox-esr no longer has audio but rest of system does. I imagine it's just because I have updated firefox and Alsa only is broken again? or because I removed several packages such as pipewire.

It must be a pipewire thing no?

But on a side note, anyone know anything about think pad EC or Kernel driver configuration in Debian?
Minor thing but curious about it of course. I can include a screen shot.