Originally Posted by montrealguy
+1 I'm looking for the same thing. The max volume on Bluetooth speaker is always 10% softer than if you plug a wire into the aux input without Bluetooth. I wonder if there is a way to boost the volume so that it matches the volume attained from a direct aux wire.
I would try to see if there may be a Xposed module that may help or if you can use a compatible kernel with volume boost. Viper Audio may also help since raising the settings within equalizer to boost vocals/bass/etc if you'd like to try as well.
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