Add to the list of experiencing this, so annoying! At one point I just stopped using CarPlay in all as I was constantly having to reboot my phone. Even got a new phone, same issue. I have since updated the Firmware too, to 1.05 and no change. Because this screeching sound still plays after disconnecting the phone from the cord, it must be an iOS issue, I would think.
The only way I have been able to resolve this bug, was this, keep bluetooth setting on the AVIC NOT to auto-connect Bluetooth devices. Ever since then, no problems at all! Not the greatest workaround as I do not want to a