Equaliser and Bluetooth

[Tim Curtis]

From the help in the Equalizers section of Audio Config.

Code:

The Equalizers are supported by MPD and the Airplay and Spotify renderers.
NOTE: The Equalizers, Crossfeed, and Polarity inversion are mutually exclusive. Enabling one will disable the SET button on the others.

You could try manipulating the ALSA EQ directly via SSH.

Code:

sudo alsamixer -D alsaequal