A further observation today: Turning the laptop on from cold, the speakers appeared in the Sound pane as expected. When testing the Videos app, the sound played normally at first but a few crackles were heard. This seemed to have coincided with setting the display to Full Screen. The sound from the speakers then disappeared completely.
On executing a restart, there was nothing listed in the "Play sound through pane". After two further restarts, the Built-in Speakers were listed but accompanied by settings for HDMI/Video port showing options of HDMI sound. This persisted after another restart. I turned on a pair of Bluetooth headphones and these subsequently appeared in the "Play sound through" panel with options for Telephony Duplex (HSP/HFP) or High Fidelity Playback (A2DP) being offered. The Test Sound button payed the test signal correctly through the headphones. When re-selecting Speakers, Built-in Audio, the correct Settings for Speakers (Balance and Greyed-out Fade and Subwoofer) appeared. The Test Sound button allowed the left and right speakers to be tested as normal. This suggests that the kernel loses its connection to the speakers which is not necessarily reset on restart. However, the operation of switching between Bluetooth headphones and the speakers does seem to restore the connection and the correct functionality. I should be happy to test out the latest kernel software but I need advice as to how to do this (files to download and commands to execute via terminal) if anyone is able to help on this. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to alsa-driver in Ubuntu. https://bugs.launchpad.net/bugs/1402194 Title: PCI/internal sound card not detected Status in alsa-driver package in Ubuntu: Incomplete Bug description: This bug relates to the internal sound hardware in a Dell XPS 13 laptop. Since accepting an upgrade to the latest Ubuntu Extra software today, the Systems Settings > Sound > Output no longer show the internal speakers, despite numerous attempts to shut down and restart. Before accepting the upgrade, the sound played normally through the speakers. Having upgraded the system from the Ubuntu 12.10 originally installed with the laptop and finding comments relating to the software drivers for the Intel WiFi and Bluetooth chip (Intel AC 7520) and touch screen, I tried out an installation straight from a Ubuntu 14.04 bootable USB stick. The system worked well enough without these drivers so I went ahead and replaced the whole installation from the USB stick and subsequently accepted the upgrade to 14.10. I tried plugging in a headset and this produced a screen allowing me to select the type of headset (mono, with or without mic or stereo). An extra entry appeared in the System Settings > Sound > Output pane allowing me to choose between the headset or the speakers and to test the audio on each one. However, unplugging the headset seemed to produce intermittent behaviour, the system being uncertain as to whether the headset was in use. This was solved by re-booting and the system and speakers behaved as expected. Now I have the situation that the speakers are not shown in the Sound > Output pane and the Output Volume slider stays at zero and is unable to be moved with the pointer. The volume control slider in the dropdown panel from the speaker symbol in the system tray appears to respond to movement from the pointer and the Fn-F11 & F12 keys. However, with no output device shown, there is no sound output to the speakers. Several attempts to restart the system have failed to restore the speaker functionality. ProblemType: Bug DistroRelease: Ubuntu 14.10 Package: alsa-base 1.0.25+dfsg-0ubuntu4 ProcVersionSignature: Ubuntu 3.16.0-28.38-generic 3.16.7-ckt1 Uname: Linux 3.16.0-28-generic x86_64 ApportVersion: 2.14.7-0ubuntu8 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: david 2172 F.... pulseaudio CurrentDesktop: Unity Date: Sat Dec 13 13:28:32 2014 InstallationDate: Installed on 2014-12-11 (1 days ago) InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2) PackageArchitecture: all ProcEnviron: LANGUAGE=en_GB:en PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_GB.UTF-8 SHELL=/bin/bash SourcePackage: alsa-driver Symptom: audio Title: PCI/internal sound card not detected UpgradeStatus: Upgraded to utopic on 2014-12-11 (1 days ago) dmi.bios.date: 09/11/2014 dmi.bios.vendor: Dell Inc. dmi.bios.version: A05 dmi.board.name: 0D13CR dmi.board.vendor: Dell Inc. dmi.board.version: A00 dmi.chassis.type: 8 dmi.chassis.vendor: Dell Inc. dmi.chassis.version: 0.1 dmi.modalias: dmi:bvnDellInc.:bvrA05:bd09/11/2014:svnDellInc.:pnXPS139333:pvr:rvnDellInc.:rn0D13CR:rvrA00:cvnDellInc.:ct8:cvr0.1: dmi.product.name: XPS13 9333 dmi.sys.vendor: Dell Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1402194/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp