[Android Head-Units] martr84:
Update: 10th Feb 2021

Got the zbox2 working with all my steering wheel controls including voice button mapped to siri.

Basically i decompiled the apk and intercept certain key-codes and changed them to the key-code zbox2 needs to trigger Siri.

Basic Steps:

1) Decompile with apktool / jadx-gui

2) Change mainActivity methods onKeyDown & onKeyUp so if keycode 86 is pressed it's substituted for keycode 1500.

When i get time i'm going to try and map the mode steering wheel button to cycle through maps, nowplaying etc which should be possible.

Context First:

i've got a px6 unit running android 9 with a canbus decoder in my mk2 audi tt.

The unit came without carplay and i've used various carplay dongles over the years and had a wireless carlinkit dongle from a previous car so decided to use that.

However using the autokit app for the carlinkit dongle i've always had audio delays on phone calls of around 2 seconds so you end up talking over each other. this is both with my current and previous head units. The dongle firmware and software is up to date using the built in updater.

Autokit works great i even managed to map all steering wheel buttons inc siri for use in Autokit its just the audio delay problem.

In regards to trying to solve my audio delay problem i bought a zbox z2 wireless carplay dongle which uses the zbox app http://www.zjinnova.com/article-34185-44239.html and the audio delay is almost not noticable basically at the level of a normal carkit.

The problem is that all the steering wheel controls work out of the box apart from siri as the zbox app has no facility to remap keys like in the autokit app (see bottom of post). Zbox only recognises the standard android media keys.

In summary i need some help?

Q: Anyone had audio delay issues on carlinkit for phone call and found a solution?

(my carlinkit dongle is from when they first released them a few years ago, i did think a newer hardware revision might help).

Q: Anyone with a zbox 2 manage to get steering wheel controls working for Siri?

Zbox 2 what ive tried so far:

Decompiled zbox 2 apk to find that it does listen to a few custom keycode events

1500 - open siri

1504 - open map

1505 - open phone

1507 - open now playing

Issued keycode event over adb while zbox is open and siri does activate.

adb shell input keyevent 1500

using tasker and autoinput together to try and grab the key that is mapped to the voice button (stop button see autokit belor for why). unsuccessful - the key doesnt get grabbed by tasker.

used tasker and media button state of stop key to then issue a shell command to send keyevent - unsucessful the key does get grabbed and issues the command but siri does not activate in the zbox app. maybe becuase i'm not root ?

next steps:

Asking for help on here?

Look at modifiying mtcd tools to send custom keyevent for siri as this does recognise the steering wheel keys being pressed but is currently limited to only send keyevents for android media keycodes.

How to map steering wheel keys in Autokit for Siri:

in wheelkeystudy app set steering wheel voice command button to stop button, needs to be these as then autokit can recongnise it.

in autokit goto advanced settings and go into key learning and the voice command button will be able to be mapped.