I completed my analysis of the Pixel 1 and Pixel 2 source code: They have been using 2 config to support low and high power consumption bluetooth audio hal There is a config option to disable audio hal and do it the legacy way but that require rooting the device or running an engineering build of Android
- (default) audio_policy_configuration.xml (this has no ASHA support, Lower power consumption on the phone) Using BluetoothAudio HAL
- audio_policy_configuration_bluetooth_legacy_hal.xml (this has ASHA support but higher power consumption) No BluetoothAudio HAL nor A2DP offload
Lets assume you are running an Engineering build of android
adb root
adb remount
adb shell mv /vendor/etc/audio_policy_configuration.xml /vendor/etc/audio_policy_configuration_old.xml
adb shell cp /vendor/etc/audio_policy_configuration_bluetooth_legacy_hal.xml /vendor/etc/audio_policy_configuration.xml
adb reboot
Background: I’m a Software Engineer with specialization in Android OS