Default to a2dp ldac_hq codec for bluethooth headset and sound distorted

[Mårten Thornberg]

I had some trouble getting my bluetooth headphones to work and I believe the culprit is the default codec that pulseaudio chooses. It appears to work ok when having no other Bluetooth devices connected, but when connecting a bluetooth mouse the audio gets distorted and begins to stutter. The offending codec is ldac_hq. I did some investigating today and found out you can change the codec in pavucontrol. Selecting ldac_sq seems to work without any issue.

I don't know what the problem with ldac_hq is, maybe bandwidth? Wasn't able to find any obvious problems in the logs, even when enabling debugging in bluez.

While investigating this I noticed others having the same issue, and it was difficult to find a way to change the codec, so maybe ldac_hq shouldn't be chosen as default?

Headphones: Sony WF-1000XM
Mouse: Logitech M590
Computer: https://www.asus.com/Laptops/For-Home/Zenbook/Zenbook-S-UX391/techspec/

$ lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 004: ID 27c6:5201 Shenzhen Goodix Technology Co.,Ltd. Fingerprint Reader
Bus 001 Device 003: ID 8087:0a2b Intel Corp. Bluetooth wireless interface
Bus 001 Device 002: ID 13d3:56b9 IMC Networks USB2.0 HD UVC WebCam
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

description: Bluetooth wireless interface
                   product: Bluetooth wireless interface
                   vendor: Intel Corp.
                   physical id: 8
                   bus info: usb@1:8
                   version: 0.10
                   capabilities: bluetooth usb-2.00
                   configuration: driver=btusb maxpower=100mA speed=12Mbit/s

Ubuntu 22.04.1 LTS
pulseaudio: 1:15.99.1+dfsg1-1ubuntu1
bluez: 5.64-0ubuntu1
pavucontrol: 5.0-2

[Sebastien Bacher (seb128)]

Thank you for your bug report, could you also register the problem upstream on https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/issues/ ? that's probably a better place to suggest a such change

[Mårten Thornberg (marrowm)]

Ok, created a new issue upstream:
https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/issues/1400

[jixbo (jixbo)]

I can confirm the issue on Ubuntu 22.04, with an Intel Wi-Fi 6 AX200 wireless card.

I have had the issue for a while with my Sony WH-1000XM3, but just realised it is a codec issue when connected a Sony SRS-XB41.

All other codecs, SBC and LDAC for various qualities, work fine. The issue is only with LDAC HQ, which is the one selected by default. The issue only happens when I have my bluetooth mouse connected.

[Launchpad Janitor (janitor)]

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

[Igor (praxis-dev)]

I have a similar problem here. After recent Ubuntu updates, I restarted my computer. The audio on the WF-1000XM4 started stuttering.

Reinstalled Bluez and PulseAudio. In the PulseAudio GUI there is a tab called Configuration. It constantly defaults codec LDAC (High Quality). When I reset it manually to LDAC (Mobile Quality) the sound is ok. After the next disconnect, the issue returns, and I solve it temporarily by changing the codec again. "Lock card to this profile" icon does not prevent it from resetting to LDAC (High Quality) again.

The issue does not involve a Bluetooth mouse, the problem is encountered with and without connection to one.

ASUSTeK COMPUTER INC. ZenBook UX393EA_UX393EA

Ubuntu 22.04.2 LTS

Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 002: ID 13d3:56cb IMC Networks USB2.0 HD IR UVC WebCam
Bus 003 Device 003: ID 8087:0026 Intel Corp. AX201 Bluetooth
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Device Descriptor:
  bLength 18
  bDescriptorType 1
  bcdUSB 2.01
  bDeviceClass 224 Wireless
  bDeviceSubClass 1 Radio Frequency
  bDeviceProtocol 1 Bluetooth
  bMaxPacketSize0 64
  idVendor 0x8087 Intel Corp.
  idProduct 0x0026 AX201 Bluetooth
  bcdDevice 0.02
  iManufacturer 0
  iProduct 0
  iSerial 0
  bNumConfigurations 1