Unable to use bluetooth headset with mic and a2dp audio

[Daniel Cerecedo]

Every device supports high fidelity audio while using headset with mic. This needs to enable two profiles at once: headset_head_unit and a2dp_sink. Right now this is impossible and I need to switch between profiles when listening to music and joining a call. In any case, the sound quality of HSP/HFP used in the headset_head_unit profile is horrible to have a call.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: pulseaudio 1:11.1-1ubuntu7.2
ProcVersionSignature: Ubuntu 4.15.0-48.51-generic 4.15.18
Uname: Linux 4.15.0-48-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.6
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Thu May 9 13:20:26 2019
InstallationDate: Installed on 2018-11-20 (169 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
SourcePackage: pulseaudio
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 12/21/2018
dmi.bios.vendor: LENOVO
dmi.bios.version: N2EET35W (1.17 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20MFCTO1WW
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40697 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrN2EET35W(1.17):bd12/21/2018:svnLENOVO:pn20MFCTO1WW:pvrThinkPadX1Extreme:rvnLENOVO:rn20MFCTO1WW:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone:
dmi.product.family: ThinkPad X1 Extreme
dmi.product.name: 20MFCTO1WW
dmi.product.version: ThinkPad X1 Extreme
dmi.sys.vendor: LENOVO

[Daniel van Vugt (vanvugt)]

> Every device supports high fidelity audio while using headset with mic. This needs to enable two profiles at once: headset_head_unit and a2dp_sink.

I really hope you are right there, but I don't know enough about the Bluetooth specs to confirm that multiple profiles can run simultaneously (at least on most devices).

Regardless, I have reopened bug 508522 covering this issue.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Hoernchen (hoernchen)]

This is not a duplicate bug, bug 508522 covers automatic switching of profiles since a2dp and hsp/hfp are mutually exclusive, there can not be two profiles active at the same time.

The true bug here is the bad voice quality, which is caused by a lack of codec negotiation. This is why bluetooth headsets will sound better connected to a random (> 4.4) android phone, which will negotiate mSBC, also known as "wide band speech", supported since HFP 1.6. This can be mistaken for "a2dp and microphone active at the same time", even though it is still a monaural configuration not related to a2dp, because it sounds so much better.

The HSP/HFP mode is using the CVSD codec which sounds like a bad gsm call, there have been attempts to merge proper codec negotiaton, but the work has stalled for some reason - see the related thread at https://www.spinics.net/lists/pulse-audio/msg29370.html and the stale patchset at https://patchwork.freedesktop.org/series/30716/

[Daniel van Vugt (vanvugt)]

Eric, it sounds like you're right about the "true bug".

However I also feel this bug report as it was originally worded is not really any different to bug 508522.

I suggest the right thing to do here is to:

1. Open a new bug for what you describe.
2. Mark bug 1828393 as a duplicate of bug 508522 again.
3. Correct any misunderstandings in bug 508522 and link to your new bug. Maybe bug 508522 will become a duplicate of your new bug.