Arch Linux

triguy

Member

Registered: 2020-11-16

Posts: 6

Website

Is Bluetooth Simultaneous HD Audio I/O Possible?

Hey guys! First post here! So I've been using Arch Linux on my new PC for a while now and I'm going for an all-wireless setup. All my peripherals are Bluetooth for a clean setup. The only annoyance I'm having is with audio. You see, my headphones sound great with H2DP Sink but HSP/HFP sounds like trash but is required for the microphone to be enabled. I was wondering if this is just a limitation of Bluetooth or if there is a way to bypass this. I know that one time I got both HD audio and low-quality microphone input working simultaneously years ago on my Ubuntu 16.04 install somehow using some hacky method but it doesn't work on anything modern. If anyone has any suggestions I'd be happy to hear them. If there's a software solution that would be ideal but if I have to use separate mic/headset combos, that is fine with me.

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"You keep on knockin' but you can't come in!" -Cheech Marin

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,728

Re: Is Bluetooth Simultaneous HD Audio I/O Possible?

This is indeed a limitation of the bluetooth protocol. There technically are some newer "standards" (read proprietary extensions) but I'm not aware of any implementations on linux.

FWIW I have a Astro A50 which is a wireless headset that does not use bluetooth and presents itself as a normal USB soundcard to the OS via a docking station. So maybe something in that direction would be an avenue to go down if you're not afraid of doing some spending.

Brocellous

Member

Registered: 2017-11-27

Posts: 145

Re: Is Bluetooth Simultaneous HD Audio I/O Possible?

This is indeed a limitation of the bluetooth protocol.

The Bluetooth 5.2 spec finally makes a standard for HQ duplex audio, though in BLE rather than Bluetooth Classic [1]. We will have to wait for supporting devices and adapters to appear though.

There technically are some newer "standards" (read proprietary extensions) but I'm not aware of any implementations on linux.

There is a tentative patchset for pulseaudio that includes, among other things, A2DP FastStream support (HQ duplex audio) [2]. Yes, FastStream is a proprietary extension from Qualcomm. AFAIK FastStream contradicts the Bluetooth A2DP spec, which was designed only for simplex transmission, in order to work. So, calling it an "extension" is rather generous. If you want to use it you should first be certain you have devices that also support it.

I don't expect these patches to land in pulse anytime in the next 6 months. If you want to try it, it seems someone has submitted an AUR package [3] that builds a PA branch with support. I haven't tried it myself.

[1] https://www.bluetooth.com/learn-about-b … /le-audio/
[2] https://gitlab.freedesktop.org/pulseaud … quests/227
[3] https://aur.archlinux.org/packages/puls … h-hsphfpd/

triguy

Member

Registered: 2020-11-16

Posts: 6

Website

Re: Is Bluetooth Simultaneous HD Audio I/O Possible?

@Brocellous and @V1del Thanks for the useful info! I figured it was a limitaton of the Bluetooth protocall but wasn't sure. I'm quite intrigued by the Pulse mod/patch though because it sounds like it is sort of the answer to my issue. I'm somewhat reluctant to test it right now because it sounds like it could present some stability problems but I will certainly see if it works! I'm hoping my AirPods will have the right specs considering they're made by one of the most influential tech giants out there and are one of their flagship products. I'll also test with my other headphones which are somewhat newer and are pretty nice, too. Thanks again for the feedback!

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"You keep on knockin' but you can't come in!" -Cheech Marin