It’s a Pioneer DEH-X6800BT, which was brand new last year and now all of a sudden discontinued. I can connect my Droid Moto Z to just about any device.... except for this god damn radio. Yes, Discovery Mode is on in the phone. If I hit the phone button, it says “READY” and then changes to “ERROR-10".

I haven’t gotten a single answer that’s worked, and now the USB I was using is coming up with ERROR-19!