Arch Linux

Shalrath

Member

Registered: 2020-05-26

Posts: 6

[SOLVED] Bluetooth Headset not recording, HSP/HFP profiles not working

Hi,

I just got my LG TONE-DFP9 full wireless earbuds and I'm trying to use them on my arch system with pipewire.

I used bluetoothctl to pair and connect them and they work fine using the profiles that can only do playback which are:
- High Fidelity Playback (A2DP Sink, codec SBC)
- High Fidelity Playback (A2DP Sink, codec SBC-XQ)

But I also want to record audio and make calls with the earbuds, so I tried to switch to these profiles:
- Headset Head Unit (HFP/HSP, codec mSBC)
- Headset Head Unit (HFP/HSP, codec CVSD)
- Headset Head Unit (HFP/HSP)

I am using pavucontrol to switch between profiles.

With all the Headset Head Unit profiles, I see the same problems:

In bluetoothctl, the device goes to an idle state:

CHG] Transport /org/bluez/hci0/dev_B8_F8_BE_0E_28_96/sep3/fd15 State: idle

This seems wrong because in the playback-profiles that do work, it goes into the active state

[CHG] Transport /org/bluez/hci0/dev_B8_F8_BE_0E_28_96/sep3/fd15 State: active

Also, in journalctl, this message pops up anytime I switch to one of the Headset Head Unit profiles:

Dez 02 20:18:02 ws2 pipewire-pulse[2094]: mod.protocol-pulse: client 0x55f75fe51970 [PulseAudio-Volumecontrol]: ERROR command:-1 (invalid) tag:4294967295 error:25 (Input/Output-Error)

The observed behavior is the following: When playing audio, everything looks as if it is playing (VU-meters are moving in pavucontrol), devices are not muted, correct output device is used, volumes are cranked up. But nothing is to be heard.
When recording, I can select the source which does show up as an input device but there is no signal (VU-meter not moving, nothing recorded). The input is not muted and the volume is up.

I have seen a guide on the arch wiki on how to use wireplumber to automatically switch profiles and codecs, but as I'm doing this manually, I think this is a solution to a problem I don't have.

I don't know how to debug further so any help is appreciated.

Last edited by Shalrath (2023-12-06 03:00:56)

Shalrath

Member

Registered: 2020-05-26

Posts: 6

Re: [SOLVED] Bluetooth Headset not recording, HSP/HFP profiles not working

I just checked with a Windows 10 VM that it is not a hardware problem.
In Windows, the profiles are named "stereo" and "Hands-Free AG Audio". With the latter profile, I'm able to record audio.

Shalrath

Member

Registered: 2020-05-26

Posts: 6

Re: [SOLVED] Bluetooth Headset not recording, HSP/HFP profiles not working

I did some more investigation using my laptop:
- It works on my Ubuntu-Laptop with an Intel AX 201 BT controller
- It does not work with the USB-Dongle on both the PC and the Laptop. The dongle has a Broadcomm 20702A0 controller

-> As the controller works on Windows, the problem must be the Linux-support of this controller.

I found some site that hinted it could be a firmware issue, so I found this:

[root@ws2 rawjaw]# dmesg | grep -i bluetooth | grep -i firmware
[    3.824549] Bluetooth: hci0: BCM: firmware Patch file not found, tried:

Installing broadcom-bt-firmware from AUR solved the issue and I can use the headset profiles.

One note though: Sound quality is bad with mSBC codec and abysmal with CVSD codec. I did some more google-reserach but it seems high-quality bidirectional audio over bluetooth is not possible in general.

Last edited by Shalrath (2023-12-06 03:00:09)