This method require flashing and rooting. After installing any mod in magisk just insert a little pin in the reset hole on the front of the radio. Otherways magisk might set factory settings back and you'll lose your data.
Many people commented on poor microphone built into the HU. I've connected the external microphone (just simple microphone that came with the HU package from seller) and it works well.
Mounted my ext microphone on the roof headliner (OEM microphone location), connected via stereo extension cable as microphones cable was not long enough. Microphone is mono and stereo extension cable was not an issue.
Here is a user who used his old external microphone: https://xdaforums.com/t/ac8259-cpu-based-hu-problems-questions-mainly-yt5760.4171219/post-84737409
Here is a search on main YT5760 thread on microphone to read about internal microphones problems:
Search results for query: microphone | XDA Forums
This member shows how to set gain on the microphone (post #122) but others couldn't find this menu (post #138).
Engineering Test Menu access code is here. Many tricky settings, so need to be careful and note your changes to not mess up the HU.
Bluetooth calls to linked phones without Android Auto/Apple CarPlay:
Use "Car Settings" -> "Volume" to set call volume and music volume independently. Usually call volumes are set much louder than music due to the narrow frequency range of calls which sounds fainter. See additional info below.
Bluetooth calls to linked phones with Android Auto/Apple CarPlay:
See #1. Issues seems to be solved with 1.75.1. No solution before, as CP/AA is an app and didn't know about "Settings" -> "Volume" settings. See additional info below.
HU's with SIM's Android native calls:
Don't have any information.
Audio DSP default setting has very high base. I set to "Rock" which is much more reasonable.
https://xdaforums.com/t/ac8259-cpu-based-hu-problems-questions-mainly-yt5760.4171219/post-87665901
There are multiple solutions and issues.
This solution is nice but have a couple of problems.
Ask Siri to call contacts easily.
Siri will read text messages and take dictations for reply.
Probably can select music by name and artist (I've not tested) and do all CarPlay voice control features.
Call has long delay to the other person (longer than Bluetooth call).
In firmwares before 1.75.1, BT call doesn't follow "Car Settings" -> "Volume" setting for voice calls. This setting is usually louder (voice is mid range frequency and need to be louder than broader frequency music). Result is CarPlays call volume is very low. You can increase volume of course but when call ends, any music playing volume with be very high.
https://xdaforums.com/t/ac8259-cpu-based-hu-problems-questions-mainly-yt5760.4171219/post-87665901
https://xdaforums.com/t/ac8259-cpu-based-hu-problems-questions-mainly-yt5760.4171219/post-86226681
This solution works well for phone calls
Put iPhone in car location where it can hear you (not pocket, bag or purse)
Ask Siri to call XXX will trigger iPhone to make call. iPhone will use Bluetooth connection for phone call (car speaker, HU mic)
No solution for messages, no solution for voice control of HU (launch apps etc.)
Bluetooth call has some delay but not as bad as CarPlay
Bluetooth call sometime have echo for the other person. Not sure of reason yet.
https://xdaforums.com/t/ac8259-cpu-based-hu-problems-questions-mainly-yt5760.4171219/post-86226681
Some HU came with paid solution by Toppal. I don't have it, but sounds like it provides Basic HU controls (launch app, volume adjust, etc.). If unactivated and wish to uninstall, it requires firmware reload
https://xdaforums.com/t/ac8259-cpu-based-hu-problems-questions-mainly-yt5760.4171219/post-86225807
https://xdaforums.com/t/ac8259-cpu-based-hu-problems-questions-mainly-yt5760.4171219/post-86226681
Besides some delay and randomly occurring echo. I've encountered issues where other person could not hear after initial call. Not sure what the issue is yet.
When using multiple apps at the same time which are using sound, the last app which sends out a sound may kill off the pre-last app playing sound; let's say you're running Spotify and Maps at the same time, Spotify gets killed as soon as Maps spits out voice directions.
To avoid killing your music app, go to "Car Settings" -> "Factory settings" -> "App Settings" -> "Audio Mutex Apps Settings" and select your music and radio apps. The only problem is that when you play music in Spotify and open Radio app, both apps will play sound at the same time mixing it. You have to remember to pause music before switching music apps.
In "Car Settings" -> "Factory settings" -> "App Settings" -> "Navigation Apps Settings" you can select your navigation apps.
Note that HU may not list some navigation apps in "Car Settings" -> "Navigation". Perhaps the app need to register itself to Android as navigation app. For example, TomTom doesn't show up after installation. Google Maps, Sygic, Here WeGo, Waze, Mapfactor Navigator, Organic Maps and Magic Earth have all been tested to show up properly.
https://xdaforums.com/t/ac8259-cpu-based-hu-problems-questions-mainly-yt5760.4171219/post-86818615
My guess is, Android doesn't provide any kind of API support for radio function. Therefore apps require their own drivers to talk to the HU's FM/AM radio hardware. As of 2022, there are no FM/AM radio apps other than XYAUTO's radio app that works with this HU. If you use a DAB+ USB receiver, you can use apps on Google Play like DABdream.
Here are 2 other DAB apps:
https://xdaforums.com/t/ac8259-cpu-based-hu-problems-questions-mainly-yt5760.4171219/post-88789855
If your car doesn't have an active antenna, you can buy an antenna booster.
Source: https://xdaforums.com/t/ac8259-cpu-based-hu-problems-questions-mainly-yt5760.4171219/post-89570933
The wireless interference seems quite high on this HU. For example, turning Bluetooth on will reduce WiFi bandwidth (link). This post claims can improve FM static although I have not tried it by myself:
I need Help please. Plus i have FM static fix | XDA Forums