I recently discovered FXSound and it’s really awesome.
If I can suggest an improvement:
It would be more intuitive in terms of UX if the big on/off button was red when the EQ is inactive and black when the EQ is active.
Indeed, I’m always confused about the current status.
A colorful button feels like “if you press me, the EQ will become active” and a black button feels like “if you want to turn off the EQ, then hit a black button”.
Don’t know if it’s just me, but I have a hard time adjusting to the other way around.