Sound plays out of the speakers and no longer the headphones. No volume control for headphones anymore.

[Vash The Stampede]

Plugging in headphones used to generate a pop up to select which audio device to play. This no longer occurs. Only get one output (speakers) in the sound controls when their used to be multiple. When plugging in headphones sound comes out of the speakers and no longer the headphones.

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: alsa-base 1.0.25+dfsg-0ubuntu5
ProcVersionSignature: Ubuntu 4.11.0-13.19-generic 4.11.12
Uname: Linux 4.11.0-13-generic x86_64
ApportVersion: 2.20.6-0ubuntu5
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: dpepe 1788 F.... pulseaudio
CurrentDesktop: GNOME
Date: Sat Aug 12 12:32:10 2017
InstallationDate: Installed on 2017-07-25 (17 days ago)
InstallationMedia: Ubuntu 17.10 "Artful Aardvark" - Alpha amd64 (20170723)
PackageArchitecture: all
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: alsa-driver
Symptom: audio
Symptom_AlsaPlaybackTest: ALSA playback test through plughw:PCH successful
Symptom_Card: Built-in Audio - HDA Intel PCH
Symptom_Jack: Black Headphone Out, Left
Symptom_PulsePlaybackTest: PulseAudio playback test successful
Symptom_Type: Only some of outputs are working
Title: [XPS 15 9550, Realtek ALC3266, Black Headphone Out, Left] Playback problem
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 05/07/2017
dmi.bios.vendor: Dell Inc.
dmi.bios.version: 1.2.25
dmi.board.name: 0N7TVV
dmi.board.vendor: Dell Inc.
dmi.board.version: A01
dmi.chassis.type: 9
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvr1.2.25:bd05/07/2017:svnDellInc.:pnXPS159550:pvr:rvnDellInc.:rn0N7TVV:rvrA01:cvnDellInc.:ct9:cvr:
dmi.product.name: XPS 15 9550
dmi.sys.vendor: Dell Inc.