[sjy]

HFP 1.6 does not solve the problem. Surprisingly, there is no solution [1]. HFP 1.6 supports "wide band speech with the mSBC codec," but this sounds terrible compared to the CD quality sound you get from the unidirectional A2DP profile. Some OSes automatically toggle from A2DP to HSP during a phone call (eg. the "auto_switch" option of PulseAudio's module-bluetooth-policy), but you can't use both profiles at the same time.

[1] https://www.ipetitions.com/petition/duplex-high-quality-audi...

This is why the wireless ModMic [2] talks about Bluetooth codecs but actually requires a custom USB wireless receiver.

[2] https://antlionaudio.com/blogs/news/introducing-modmic-wirel...

[makomk]

Yeah. It's possible that Bluetooth LE Audio could improve this, we'll see once they finally get around to releasing the specs. It certainly sounds like it's designed to support bidirectional audio links without the stupid HSP/HFP divide of classic Bluetooth. (There's more mainstream demand for this feature now due to things like voice assistants.)

[nobrains]

What about dedicated Bluetooth headsets for phones, like plantronics? Aren't they supposed to work bidirectional with high quality audio? Or do they also use the standard Bluetooth profiles/protocols?

[makomk]

Bluetooth headsets like the ones Plantronics make are designed for making phone calls, and the limitations of the standard Bluetooth headset protocol weren't a problem for that because standard phone lines were monoaural with the exact same frequency response and bit depth limits so you weren't losing anything extra. The trouble is that people want to use Bluetooth audio for things like gaming, video conferencing, using voice assistants whilst playing music etc which have much higher quality audio. Also, phone calls themselves are slowly improving too with things like HD Voice.