2009 M3 Driver Side Rear Speaker doesn't work

2009 E92 with iDrive, and pretty sure I have the hi-fi system, there are 11 speakers and they are a gold color.

Driver side Rear speaker, DOA. Uninstalled it, ran it to a voltmeter, saw some current, thought it was the speaker itself. Replaced it. Still DOA.

Not sure what to do next, or where to check? Do these speakers require the mid and the high to be hooked up to work properly? I've not checked the high, but figured since the mid itself wasn't working, that was the culprit...