I had this issue too. It was fixed by linux-firmware 1.161.1 in the system76 ppa
-- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to alsa-driver in Ubuntu. https://bugs.launchpad.net/bugs/1647119 Title: audio card is not detected Status in alsa-driver package in Ubuntu: New Bug description: Sound stops working on a laptop running Ubuntu. When the laptop is left alone overnight, the sound works the next day. I'm not quite sure why this would happen. Dummy Ouput is the only device shown once the sound stops working. "aplay -l" command shows the following: aplay: device_list:268: no soundcards found... ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: alsa-base 1.0.25+dfsg-0ubuntu5 ProcVersionSignature: Ubuntu 4.4.0-51.72-generic 4.4.30 Uname: Linux 4.4.0-51-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: CurrentDesktop: Unity Date: Sat Dec 3 22:37:12 2016 EcryptfsInUse: Yes PackageArchitecture: all SourcePackage: alsa-driver Symptom: audio Title: PCI/internal sound card not detected UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 10/11/2016 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 5.12 dmi.board.asset.tag: Tag 12345 dmi.board.name: N24_25BU dmi.board.vendor: Notebook dmi.board.version: lemu7 dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 10 dmi.chassis.vendor: Notebook dmi.chassis.version: N/A dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr5.12:bd10/11/2016:svnNotebook:pnN24_25BU:pvrlemu7:rvnNotebook:rnN24_25BU:rvrlemu7:cvnNotebook:ct10:cvrN/A: dmi.product.name: N24_25BU dmi.product.version: lemu7 dmi.sys.vendor: Notebook To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1647119/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
