[Android Automotive OS] Tachi91:
Update:

Borrowing a buddies kitchen junk drawer android phone, I was able to confirm AA does have permissions to overly on top of the sidebar. I only ever saw AA running with Spotify on the right side in random social media potato phone posts. I assumed since the radio allows for Spotify to be installed from the AAOS PlayStore. That it was also allowed its own widget on the side panel. Separate from AAs Spotify client. I don't have an account and never bothered trying.

The MGears MStick3 I received also confirms that AA is allowed to expand further compared to CarPlay. It arrived sooner than expected so I shifted gears away from the Pi 4 attempt. It's running Android 10 and recognized by the radio as AA. Whatever custom launcher it uses is displayed with the same real estate that true AA is given. As far as the radio is concerned it's an Android Phone projecting AA.

The dongle daisy chain works for the most part. With the MStick3 projecting "Android Auto" and the side loaded AutoKit displaying the iPhones CarPlay projection via Carlink. CarPlay does render properly on the radio. As seen in my previous post (#8).

The biggest issue this dongle daisy chain has is audio routing. What devices receives what audio depending on what's happening.

- Phone Calls : iPhone defaults to "CarPlay" [CarPlay => Carlink => MStick3 => Radio] as the audio output. However there is no audio from the speakers. If the iPhone is connected to the truck via BT, It the truck is listed as an optional output device. [Phone => Radio] Which works for phone calls and at times this selection carries over to other calls. It does require the manual intervention occasionally.

- Music / Podcast: audio is passed through [CarPlay => Carlink => MStick3 => Radio] without any major issues. So that audio path works.

- Siri interaction: While you can trigger Siri or have it read a message and prompt you for a response. It cannot hear you and times out. I'm thinking there's a software break in the path. Maybe stuck process preventing access to the Trucks microphone? AutoKit does have an option for Microphone routing, but the only options are [CAR], [PHONE], [BOX]. Neither of which work and [BOX] is not supported. The MStick itself has two options for Microphone pass through for troubleshooting. The default is set to "Android Auto Mode" while the other is, Radio? Neither made a difference.

- - - The strange part is the last few days I have been randomly attempting to interact via voice with no success. Until yesterday when it worked for one single interaction. Weirdly enough this happened at the same time that all audio was being labeled as "Navigation" audio by the radio. It was low quality normally heard during Turn-by-Turn directions. I tried doing it again, but it had no reaction to me talking like before. Whatever process worked partially correct was reset when the successful interaction was complete.

If metadata in the audio stream or another process is used to define the individual audio between the car and the phone. It's hitting a road block. I'll have to setup my Pi with Android again, install AutoKit, and verify that both Audio Output and Microphone input are recognized by CarPlay. That would confirm that the Carlink itself supports the actions without issue. I haven't tested more then the one time, but with just the MStick3 connected the virtual keyboards dictation did not work. The car radio itself does not have BT audio options besides what's in Developer Options,but most of those options don't do anything on this truck,