Couple things, I'm assuming you've tried other cables right? I have no issues with charging from the ports but I'm on the latest 3.4 (20237) version and I still have android auto issues. For example, in the previous release and this release, almost every time I shut off the car, then turn it back on with a Pixel 3 connected the whole time, the Sync display is completely black. I have to unplug the phone and reconnect it to get the head unit to start working again.
Additionally, as many others have, I have a lot of issues with incoming calls when connected via usb and android auto. Specifically, there's no audio when you answer a call while connected, if I disconnect the usb cable (which stops AA), bluetooth picks up and starts working almost immediately.