[BUG] ALC295 internal speaker silent on Panasonic Let's Note CF-SV8 (PCI subsys 10f7:8338)

[kay-ws <a3.works@gmail.com>]

Hi,

Internal speaker is silent on a Panasonic Let's Note CF-SV8-2
(Realtek ALC295, PCI subsystem 10f7:8338), while the headphone jack
works correctly.

Hardware confirmed healthy:
  - Internal speaker plays sound under Windows 10
  - Panasonic BIOS HW self-test reports speaker OK

Linux side:
  - Kernel 7.0.2-2-cachyos (CachyOS / Arch)
  - ALSA 1.2.15.2, PipeWire 1.6.4

The driver picks no quirk fixup for this subsys:

  ALC295: picked fixup  for PCI SSID 10f7:8338   <- empty fixup name

PCM data reaches Pin 0x14 (Audio Output 0x02 has stream=1 during
playback, same as 0x03 which feeds the working headphone), Pin-ctls
is OUT, amp is unmuted, but no audio is produced through the
internal speaker.

Tried with no effect:
  - options snd_hda_intel model=thinkpad (fixup chain runs)
  - hda-verb 0x14 SET_EAPD_BTLENABLE 0x02
  - hda-verb 0x01 SET_GPIO_MASK/DIRECTION/DATA 0x03
  - WirePlumber profile output:analog-stereo (non-duplex)

Full alsa-info.sh dump:
  http://alsa-project.org/db/?f=546e2c9fc0e2261cb6d8a7c837f8c3f54f771064

Could a fixup entry for PCI SSID 10f7:8338 be added to the alc269
quirk table? I'm happy to test patches and try Realtek coef
sequences if suggested.

Thanks,
kay-ws