Hello everyone. This is my first post on this forum, so please let me know if I done something wrong. Also, english is not my native language, so typos are possible.

My system:
dell inspiron 5767 intel core i3-6006U laptop
debian stretch installation via default cd image on empty SSD
only stable repositories are used for updates, no backports

Problem:
No sound can be heard through built-in speakers or headphones

Background:

some outputs:
eld@eldred:~$ lspci -v
00:1f.3 Audio device: Intel Corporation Sunrise Point-LP HD Audio (rev 21)
Subsystem: Dell Sunrise Point-LP HD Audio
Flags: bus master, fast devsel, latency 32, IRQ 282
Memory at d1228000 (64-bit, non-prefetchable) [size=16K]
Memory at d1200000 (64-bit, non-prefetchable) [size=64K]
Capabilities: <access denied>
Kernel driver in use: snd_hda_intel
Kernel modules: snd_hda_intel, snd_soc_skl

eld@eldred:~$ lsmod |grep snd
snd_hda_codec_hdmi 49152 1
snd_soc_skl 65536 0
snd_soc_skl_ipc 45056 1 snd_soc_skl
snd_soc_sst_ipc 16384 1 snd_soc_skl_ipc
snd_soc_sst_dsp 32768 1 snd_soc_skl_ipc
snd_hda_ext_core 28672 1 snd_soc_skl
snd_soc_sst_match 16384 1 snd_soc_skl
snd_soc_core 212992 1 snd_soc_skl
snd_compress 20480 1 snd_soc_core
snd_hda_intel 36864 0
snd_hda_codec 135168 2 snd_hda_intel,snd_hda_codec_hdmi
snd_hda_core 86016 5 snd_hda_intel,snd_hda_codec,snd_hda_ext_core,snd_soc_skl,snd_hda_codec_hdmi
snd_hwdep 16384 1 snd_hda_codec
snd_pcm 110592 7 snd_hda_intel,snd_hda_codec,snd_hda_ext_core,snd_hda_core,snd_soc_skl,snd_hda_codec_hdmi,snd_soc_cor e
snd_timer 32768 1 snd_pcm
snd 86016 8 snd_compress,snd_hda_intel,snd_hwdep,snd_hda_codec,snd_timer,snd_hda_codec_hdmi,snd_soc_core,snd_pcm
soundcore 16384 1 snd

eld@eldred:~$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 3: HDMI 0 [HDMI 0]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 7: HDMI 1 [HDMI 1]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 8: HDMI 2 [HDMI 2]
Subdevices: 1/1
Subdevice #0: subdevice #0

eld@eldred:~$ speaker-test

speaker-test 1.1.3

Playback device is default
Stream parameters are 48000Hz, S16_LE, 1 channels
Using 16 octaves of pink noise
Playback open error: -2,No such file or directory

I believe sound card drivers are loaded, but alsa does not detect analog output devices, only HDMI. Alsamixer also doesn't show analog channels.
No other software like pulseaudio currently installed.
No additional alsa configuration files used: no /home/.asoundrc or /etc/asound.conf. Alsa should run in its default state.
All updates are applied through synaptic.

Also tried to install pulseaudio, and speakers worked with it, so hardware isn't broken. However, when I plugged in headphones jack, sound was gone and applications like mplayer failed to start, appearing as zombie process in task manager and ignoring normal kill signals. Currently I removed pulseaudio and trying to figure out how to make do with alsa only.

Immediately after debian installation sound worked fine(alsa only). I can't remember exactly what i did right before this problem, because i didn't need sound very often. For example, i tried to install wine, but later removed it after attempted windows application caused complete system hanging and required cold restart. I certainly didn't alter any sound-related configuration on purpose. Could be that I accidently removed some alsa-related package.

As you can see, I am a noob with linux and I would be very grateful for any help. Thank you for actually reading to this point and sorry for my grammar.

Update: problem is fixed.

Missing sound after plugging in headphones was due to a codec probing problem, as described here: https://www.kernel.org/doc/html/v4.1...dio/notes.html

Specifying probe_mask option (0x101 for me) in conf file solved it.

Okay, I am removing "solved" tag, because something really weird is going on.

After setting probe_mask to 0x101 sound was working fine for a few days. Codec proc-file located in /proc/asound/card0/ reported proper information about codec, which is not reproducible now. After plugging in headphone jack again during movie playback all sound was gone and said proc-file became almost empty(again, I didn't save that output, regretfully). After rebooting (because mpv player could not be terminated) all I could see was:

eld@eldred:~$ su -c dmesg |grep snd
Password:
[ 18.146751] snd_hda_intel 0000:00:1f.3: enabling device (0000 -> 0002)
[ 18.146956] snd_hda_intel 0000:00:1f.3: codec_mask forced to 0x1
[ 18.259761] snd_hda_intel 0000:00:1f.3: bound 0000:00:02.0 (ops i915_audio_component_bind_ops [i915])
[ 21.315102] snd_hda_intel 0000:00:1f.3: azx_get_response timeout, switching to polling mode: last cmd=0x000f0000
[ 22.319269] snd_hda_intel 0000:00:1f.3: No response from codec, disabling MSI: last cmd=0x000f0000
[ 23.327268] snd_hda_intel 0000:00:1f.3: Codec #0 probe error; disabling it...
[ 23.331963] snd_hda_intel 0000:00:1f.3: no codecs initialized

/proc/asound/card0/ folder was completely empty, and no sound card was detected by alsa/pulseaudio

eld@eldred:~$ aplay -l
aplay: device_list:270: no soundcards found...

The same happens if I remove codec_mask forcing. However, lspci still lists device name properly:

00:1f.3 Audio device: Intel Corporation Sunrise Point-LP HD Audio (rev 21)
Subsystem: Dell Sunrise Point-LP HD Audio
Flags: bus master, fast devsel, latency 32, IRQ 16
Memory at d1228000 (64-bit, non-prefetchable) [size=16K]
Memory at d1200000 (64-bit, non-prefetchable) [size=64K]
Capabilities: [50] Power Management version 3
Capabilities: [60] MSI: Enable- Count=1/1 Maskable- 64bit+
Kernel driver in use: snd_hda_intel
Kernel modules: snd_hda_intel, snd_soc_skl

In BIOS, audio is set to "enabled", however, in "system information" summary tab in BIOS, audio controller is listed as "none"(single word), as opposed to all other hardware information next to it. Can post a screenshot if necessary.

This dell inspiron 5767 is a new (bought in 2018) laptop, and no hardware manipulations were performed on it other than replacing internal HDD with SSD and installing debian on it.

I am out of ideas here, and really need help.

Problem is fixed. Again...

Guess I,ll be the laughing stock of the forum, hope I entertained you well).

I really believed that 3-conductor plug should have no trouble on 4-conductor jacks (at least on modern devices). The joke is that my 3-pin headphones worked for last 3 mounths without trouble with this laptop. I was lucky that hardware survived this, and that new 4-pin headphones plug/unplug correctly (for now, at least).