A direct output is required to deliver the track's multi-channel content to the output HAL rather than sending it over as a primary mixer output that delivers stereo.
In case of an audio track created with DEEP_BUFFER input flag in order to enable the power saving mode, a DIRECT output cannot be opened for multi-channel outputs.
With dynamic audio policy enabled, a failure to open direct outputs results in a fall-through primary mix output delivering stereo output instead of intended multi-channel outputs to the downstream HAL.
In order to prioritize channel fidelity over the power saving mode, clear the DEEP_BUFFER request while requesting for a direct output. This way the audio HAL gets all the channels delivered downstream.
Description
In case of an audio track created with DEEP_BUFFER input flag in order to enable the power saving mode, a DIRECT output cannot be opened for multi-channel outputs.
With dynamic audio policy enabled, a failure to open direct outputs results in a fall-through primary mix output delivering stereo output instead of intended multi-channel outputs to the downstream HAL.
Following CL restricts opening a DIRECT output with DEEP_BUFFER enabled :
In order to prioritize channel fidelity over the power saving mode, clear the DEEP_BUFFER request while requesting for a direct output. This way the audio HAL gets all the channels delivered downstream.
This is seen in Android-15 onwards.