Ubuntu as bluetooth speaker - volume on bluetooth client ignored

[Krister Swenson]

I'm using my 20.04 system as a media center. It's got a bluetooth adapter plugged into a USB port. I can connect to the system with my phone and ipad as an A2DP source and play music.

The problem is that the volume on the source device is not respected

When the volume on the source device goes to 0, the sound is muted as expected, but any other volume on the source device leads to the same volume on the Ubuntu server. The only way to adjust the volume is from the server.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: pulseaudio 1:13.99.1-1ubuntu3.2
ProcVersionSignature: Ubuntu 5.4.0-31.35-generic 5.4.34
Uname: Linux 5.4.0-31-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.20.11-0ubuntu27
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: kodi 1455 F.... pulseaudio
 /dev/snd/controlC0: kodi 1455 F.... pulseaudio
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Fri May 22 16:42:57 2020
InstallationDate: Installed on 2015-09-30 (1695 days ago)
InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422)
SourcePackage: pulseaudio
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 03/04/2015
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 2404
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: H97M-PLUS
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: Rev X.0x
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: To Be Filled By O.E.M.
dmi.chassis.version: To Be Filled By O.E.M.
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr2404:bd03/04/2015:svnASUS:pnAllSeries:pvrSystemVersion:rvnASUSTeKCOMPUTERINC.:rnH97M-PLUS:rvrRevX.0x:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.:
dmi.product.family: ASUS MB
dmi.product.name: All Series
dmi.product.sku: All
dmi.product.version: System Version
dmi.sys.vendor: ASUS

[Krister Swenson (thekswenson)]

Would anyone have an idea as to a workaround, or an idea of how I could debug this problem?

[Krister Swenson (thekswenson)]

Is this bug filed against the correct package?

[Sebastien Bacher (seb128)]

Thank you for your bug report, pulseaudio is probably the right component there yes, you might to report it upstream directly on https://gitlab.freedesktop.org/pulseaudio/pulseaudio/issues/ though to increase your chances to get a reply

[Krister Swenson (thekswenson)]

Thanks Sebastien, I've posted this bug upstream as https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/issues/1057

I've also noted some peculiarities with respect to different clients:

- computer: host/sink/server volume remains constant until source/client goes to 0, then silent
- Android phone: sink volume constant until the lowest 10% on source, then the volume decreases in 4 increments.
- ipad: sink volume constant no matter what the volume on the ipad source.