After updating from jessie to stretch this week I found my heaphone jack no longer outputs sound, though my built in speakers work just fine. The puzzling thing is that everything seems to be in order as far as I can tell. Pavucontrol shows output to the headphones device, but I don't hear anything. When I mute or unmute I can hear a pop in the headphones. The device is detected and activated when I plug in or remove headphones.
System Info: Lenovo Carbon X1, Debian Stretch, Card is HDA Intel PCH. my alsa-info.sh
What works: Headphone Detection, Pavucontrol, Builtin Speaker, I hear a pop when muting/unmuting.
I've tried the answers to this question. I've tried purging and reinstalling alsa and pulse audio.
[Element Speaker] switch = on volume = ignore
/usr/share/pulseaudio/alsa-mixer/paths/analog-output-headphones.conf is a good idea but does not solve my problem.