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I am aiming for low latency audio in Android M and using Superpowered sdk. Simply routing internal microphone to internal speaker works flawlessly - By using the general guidelines to enable high performance audio (http://googlesamples.github.io/android-audio-high-performance).

My android device has a native SR of 48Ks/s. When I pair it with an external bluetooth speaker, the output gets automatically redirected to the external speaker. As I try to run the same application while connected, I get the following message:

W/AudioTrack: AUDIO_OUTPUT_FLAG_FAST denied by client; transfer 1, track 48000 Hz, output 44100 Hz

and the horrible big latency is back on.

I assume the problem relies on the BT audio module of the android device having a SR of 44.1Ks/s and making it incompatible to the rest of the link being 48K. I tried changing the SR to 44.1K but, as expected, I got a similiar denial (AUDIO_INPUT_FLAG_FAST) with different reason "track 44100 Hz, primary 48000 Hz".

Is there a way to change the SR in the BT audio module so it matches the rest of the link SRs to enable low latency audio?

Alejandro
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    I'm afraid you can't have low latency with Bluetooth, because a) it's wireless, and thus has it's own non-negligible delay and b) it uses it's own codec so your data is recompressed anyways. All the low latency solutions use wired connection (e.g. USB). – Mikhail Naganov Sep 16 '16 at 14:41

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