Bluetooth audio does not work

• /e/ version: e-0.8-n-2020041549770-dev-cancro
• Device model: https://images.ecloud.global/dev/cancro/e-0.8-n-2020041549770-dev-cancro.zip
• When it started to occur: -
• Reproducible with the last /e/ version: yes
• Reproducible with LineageOS: -

Summary

Bluetooth audio does not work on Mi4/cancro.

The problem

Steps to reproduce

1. Make clean install of /e/
2. Pair Bluetooth audio device, e.g., headset
3. Play sound or music

What is the current behavior?

Device is connected, but there is no sound. It looks like the sound is played, but you cannot hear it. See also: https://community.e.foundation/t/bluetooth-connection-not-working-in-a-strange-way/12579 https://community.e.foundation/t/bluetooth-issue-help-me-this-is-stopping-me-from-using-e/12736 (different devices)

What is the expected correct behavior?

Sound is played.

Technical informations