[erdewit]

When playing FLAC music over aptX HD, the next step for improvement is to avoid any resampling. The music is generally at 44.1 kHz and the default for Android is 48 kHz. It requires root to change the audio config file to 44100, and it's also necessary to change the bluetooth settings (in the developer options).

Something similar goes for Linux.

The resampling shouldn't matter much in theory, but in practice it's pretty noticeable. It seems to be optimized for CPU usage instead of audio quality.

[userbinator]

It seems to be optimized for CPU usage instead of audio quality.

Presumably on an Android phone, it makes sense to lower CPU usage (and thus prolong battery life) rather than go for the best audio quality.