Sorry for the subject not-so-specific but I hope this message can start a first iteration to better focus my problem.
The problem in short: no sound card available to pulsaudio, while ALSA seems to correctly detect HDA Intel PCH.
To make the problem more puzzling, in the same laptop with an ubuntu live (with kernel 4.15) audio works correctly.
This means that the soundcard IS supported in some way (though I don't know the ubuntu way). Tried to test if the cause is kernel regression: installed kernel 4.15 (from debian snapshot), but the song remains the same (in this case the song is the sound of silence).
This drives me crazy.
I'm ready to perform any diagnostics/tests you could imagine to get my audio back.
Below I report the info on hardware and kernel.
Please help!!!
-- hardware: Lenovo Thinkpad X270;
-- soundcard (from lspci) 00:1f.3 Audio device: Intel Corporation Sunrise Point-LP HD Audio (rev 21)
-- debian_version: sid
-- kernel: 4.18.0-2-amd64
-- kernel modules ( lsmod | grep snd)
snd_hrtimer 16384 1
snd_seq_midi 16384 0
snd_seq_midi_event 16384 1 snd_seq_midi
snd_rawmidi 40960 1 snd_seq_midi
snd_seq 81920 3 snd_seq_midi,snd_seq_midi_event
snd_seq_device 16384 3 snd_seq,snd_seq_midi,snd_rawmidi
snd_hda_codec_hdmi 61440 1
snd_hda_codec_realtek 110592 1
snd_hda_codec_generic 86016 1 snd_hda_codec_realtek
snd_soc_skl 118784 0
snd_soc_skl_ipc 73728 1 snd_soc_skl
snd_soc_sst_ipc 16384 1 snd_soc_skl_ipc
snd_soc_sst_dsp 36864 1 snd_soc_skl_ipc
snd_hda_ext_core 28672 1 snd_soc_skl
snd_soc_acpi 16384 1 snd_soc_skl
snd_soc_core 253952 1 snd_soc_skl
snd_compress 24576 1 snd_soc_core
snd_hda_intel 45056 3
snd_hda_codec 151552 4 snd_hda_codec_generic,snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec_realtek
snd_hda_core 94208 7 snd_hda_codec_generic,snd_hda_codec_hdmi,snd_hda_intel,snd_hda_ext_core,snd_hda_codec,snd_hda_codec_realtek,snd_soc_skl
snd_hwdep 20480 1 snd_hda_codec
snd_pcm_oss 61440 0
snd_mixer_oss 28672 1 snd_pcm_oss
snd_pcm 118784 9 snd_hda_codec_hdmi,snd_hda_intel,snd_hda_ext_core,snd_hda_codec,snd_pcm_oss,snd_soc_core,snd_soc_skl,snd_hda_core
snd_timer 36864 4 snd_seq,snd_hrtimer,snd_pcm
snd 94208 21 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_pcm_oss,thinkpad_acpi,snd_soc_core,snd_pcm,snd_rawmidi,snd_mixer_oss
soundcore 16384 1 snd
alsamixer see teo sound cards:
-- default (pulseaudio)
-- HDA Intel PCH
for this second card (when selected with F6), alsamixer displays a list (relatively rich) of audio I/O controls
HOWEVER, pulsaudio only sees a (useless) dummy output, saying "no cards available for configuration" in the Configuration tab.