No sound from internal speakers on Tecno Megabook K16S AMD with ALC269VC (Subsystem ID: 0x1f5c0018)

alsa-project/alsa-lib issue #512 was opened from lemirantos:

Hello,
I'm experiencing no sound from internal speakers on Tecno Megabook K16S AMD (2024 model) with Realtek ALC269VC codec.

Hardware:
Laptop: Tecno Megabook K16S AMD 7000
CPU: AMD Ryzen 7 7735HS with Radeon Graphics
Audio codec: Realtek ALC269VC
Subsystem ID: 0x1f5c0018
Kernel: 6.19.10-300.fc44.x86_64
Distribution: Fedora 44 KDE Plasma 6.6.4

Problem:
Internal speakers produce no sound. Headphones work when connected. Bluetooth audio works.
Diagnostic findings:
Codec detects speakers (Node 0x14: "Speaker at Int N/A")
Speaker playback volume control exists and is set to 80%
However, the amplifier on pin 0x14 shows: Amp-Out vals: [0x00 0x00] (muted/zero)
Manual attempts to enable amplifier with hda-verb don't produce sound
EAPD is present but enabling it doesn't help

What I tried:
options snd-hda-intel model=auto - no effect
options snd-hda-intel model=laptop - no effect
options snd-hda-intel model=alc269-dmic - no effect
options snd-hda-intel model=dell-headset-multi - no effect
options snd-hda-intel model=hp-dv7-4000 - no effect
options snd-hda-intel model=lenovo-101e - no effect
options snd-hda-intel model=asus-mode1 - no effect
options snd-hda-intel model=alc269-vieo - no effect
options snd-hda-intel power_save=0 - no effect
options snd-hda-intel dmic_detect=0 - no effect
options snd-hda-intel enable_msi=1 - no effect
Manual hda-verb /dev/snd/hwC1D0 0x14 SET_AMP_GAIN_MUTE 0x7f - no effect
Manual hda-verb /dev/snd/hwC1D0 0x14 SET_EAPD_BTLENABLE 0x2 - no effect
Tested with latest mainline kernel 6.19 - no effect
Additional info:
Bluetooth audio works fine
HDMI audio works
Headphone jack detection works (system detects when headphones are plugged in)
USB audio cards work
This appears to be a missing quirk for Tecno laptops with ALC269VC. The amplifier on the speaker pin needs to be properly initialized.
Full ALSA info: https://alsa-project.org/db/?f=726c125be3aa830e4c8c9c454596b9b6abaf739c

[codec-info.txt](https://github.com/user-attachments/files/29062481/codec-info.txt)

Thank you!

Issue URL     : https://github.com/alsa-project/alsa-lib/issues/512
Repository URL: https://github.com/alsa-project/alsa-lib