Spotify needs a feature where EQ is set to the method of playing sound. So automagically the EQ resets to your car, phone, earbuds, etc.
Device detection is tragic, and it requires machine learning device metadata to get right. A lot of listeners use an AUX input for their car stereo sessions, which can be mistaken for regular AUX playback.
Would love to have a specific filter that can be applied to different apps (preferable at the hw / audio interface level).