[Android Auto General] camilojones:
Calls audio through car speakers instead Bluetooth Problem. Sony XAV-AX100 + Moto G5

The Problem:

When I connect via USB my phone to my Sony XAV-AX100 head unit, the audio from Play music, Waze, Spotify works as should, but when I try to make a call, the call audio is routed to the phone speaker. Switching to "Bluetooth" icon in the dialer interface doesn't work, also sometimes the music (Play music) won't resume after hanging up. This happens 50% of the times when I make a call. Also, I realized when this happens, unplugging my phone and switching to the head unit interface, the music resumes but with abysmal jagged sound. Is like somehow the Bluetooth communication between the phone and the head unit has crashed.

Also, there are times when this happens, and unplugging my phone from the USB cable and switching to the head unit interface, It shows that the call is still running on the head unit dialer interface screen but completely frozen and can't hang up, I just have to wait for the call drops. Restarting the Headunit is the only way to temporarily fix the BT conflict/problem.

Is impossible to replicate the issue, sometimes I can make 10-15 calls without any issues, and sometimes this happens after the first call. Also happens to my wife's phone (same model)

Almost a solution:

I realized the issue is more often when I start the car / turn on the head unit with the phone already plugged into the USB cable, so lately I have been plugging the phone into the USB cable ONLY AFTER the head unit ends the booting process and shows the main Sony screen interface, and the phone has been connected via Bluetooth to the HU. Then, I plug the phone into the USB cable to launch AA. Somehow with this method, the issue is not as frequent and it happens just 20% of the times.... but still happens :(

Workarounds: (no solution)

Reinstall AA, delete BT connection, removed AA connected cars, Clear BT cahe and data, set AA auto start ON/OFF, set AA Bluetooth ON/OFF, AA limit WiFi.... (all possible toggles combinations), Clear phone cache, Head unit factory reset, etc.

Also, I have tried to turn OFF/ON the phone Bluetooth while AA is running and letting it reconnect, doesn't work.

Any solutions, workarounds????

PLEASE HELP!!!!!!

Thank you!

******* UPDATE 1 week afer:

Still having the issue 50% of the time.

Upgraded Head unit latest FW.

I did the "let AA setup BT" method (a million times), after forgetting all cars and unpairing all BT connections. Also tried disabling phone BT before plugging to the USB cable. No happy endings!

Is like a Russian roulette, Sometimes the issue occurs after trying to hang up the first call, sometimes after the 3rth call, and sometimes it never happens, like there's not an events pattern that triggers the glitch.

Next steps:

Will install and old AA APK (from october 2017), at that time I remember the HU worked perfectly, will see if this is related to some recent app updates.

By the way, I tried to replicate the issue without using AA, just connected to the head unit via BT, and with the HU default dialer, I made like 30 calls to the voicemail without any problem. So for this scenario, the hang-up button is actually hanging up the calls and resuming the music (like it should).

Thanks guys!

Car / head unit make & model: Sony XAV-AX100

Phone make & model: Moto G5 Plus

Android OS version: Android 7.0

Android Auto app version: 3.3.582063

Google Play services version: 12.6.85 (040308-197041431)