JBL stereo drawing current while off
 

My battery recently started dying after being parked for more than 3 days, and I was easily able to track the issue down to the main radio fuse: drain while off and sitting for awhile immediately drops from 80mA to ~15mA with that fuse pulled; none of the others drop more than 10mA when pulled.

I've search all the similar posts, and people mention the factory JBL stereo's amp -- which my runner has -- being the likely problem.

I'm having trouble narrowing down where the specific problem might be within the radio system, and what my options are. Is it the sub amp, and is there a separate fuse or plug somewhere for that which I can remove for now? I was reasonably happy with the factory sound system, but suppose replacing/upgrading it all could be worthwhile if there's no easy+cheap fix for this new parasitic drain. Any experience/advice with this appreciated, thank you.