I'm seeing the same thing. Every once in a while, the sound devices disappear from the sound settings. However, for me the sound usually stops working, and then when I open VLC, it throws sound errors.
This bug seems to be important. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to pulseaudio in Ubuntu. https://bugs.launchpad.net/bugs/1574792 Title: sound devices disappear from sound settings Status in pulseaudio package in Ubuntu: Confirmed Bug description: Sound devices disappear from the sound settings however sound is still working. pulseaudio --kill pulse audio --start restore them back to the sound settings. In rear cases, it cannot be started "daemon startup failed". This can happen at any time without a reason, also sometimes happen when plugging headphones or connecting bluetooth speaker. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: pulseaudio 1:8.0-0ubuntu3 ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6 Uname: Linux 4.4.0-21-generic x86_64 ApportVersion: 2.20.1-0ubuntu2 Architecture: amd64 CurrentDesktop: Unity Date: Tue Apr 26 01:02:04 2016 InstallationDate: Installed on 2016-04-24 (1 days ago) InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) SourcePackage: pulseaudio UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 09/04/2014 dmi.bios.vendor: coreboot dmi.bios.version: 4.0-6588-g4acd8ea-dirty dmi.board.name: Peppy dmi.board.vendor: GOOGLE dmi.board.version: 1.0 dmi.chassis.type: 3 dmi.chassis.vendor: GOOGLE dmi.modalias: dmi:bvncoreboot:bvr4.0-6588-g4acd8ea-dirty:bd09/04/2014:svnGOOGLE:pnPeppy:pvr1.0:rvnGOOGLE:rnPeppy:rvr1.0:cvnGOOGLE:ct3:cvr: dmi.product.name: Peppy dmi.product.version: 1.0 dmi.sys.vendor: GOOGLE To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/1574792/+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