Exploring the problem of popping sounds

dudu-lai no it was not connected, i soldered the two after i received your feedback regarding this cable needed to be connected to the harness. The harness did not have (AMPC) this pin was empty. so i had to take this cable from another harness to be able to connect it to the amp control cable.
here is what the wiring harness looked like prior

dudu-lai My harness did not come with an exposed ACC wire.

dudu-lai I should depin this from the canbus connector?

dudu-lai no. Without the canbus you get no sound , the Subaru outback with Harman kardon amplifier required Canbus to get audio with after market headunits. Here is the pin diagram for the original harness

Regards

dudu-lai should i remove this Amp C connection from my harness since you mentioned this amplifier is not controlled via this cable? and what is the solution in this case. I have had 2 different Android Based headunits in the pass on my subaru outback connected with the same cambus and harness combination and they did not cause the thumping or popping noise on boot. so i can confirm this is possible i just dont know with the DUDU7 what is the fix here. thanks for your feedback and support.

dudu-lai
so you are basically trying to control the powering of the oem amplifier using the C control cable. my CANBUS options do not show this power management control for the amplifier. see attached pictures. the hardware i am using is simple soft xp. I will have to take the headunit apart again to try this, please confirm . (side note , since i lasted posted , I updated the headunit to 3.5 beta 3. did not solve any of my issues. so i factory reverted back to 3.5 december release. so right now the unit is in clean state no mods.

Bradha333 Same issue with my subaru 2017, you have to keep the volume super low or your speakers start crackling, and they can get damaged. This is definitely an issue with double amplification. i have lowered the power output dudu7 amp is using but then then issue is the sound is too low. and some songs with different audio levels come at a ok level, others you cant hear and then you get one that blows your speakers. This also creates additional issues if you enable sound profiles. or have the road noise based audio correction features on. I think the answer here would be to be able to disable the Dudu7 internal amp. This is something i have done with other android based headunits in the past which has solve this issues, allowing you to still use equalization and pass the signal to the OEM harman kardon amplifier without pre amplification on it. but i have not found any way to disable the internal dudu7 amp. just lower its sound output which is still pre amped.
Maybe someone here knows if there is a way to disable the internal amplifier, and another benefit of that is lower temperatures on the dudu7 itself which is a plus.

dudu-lai Removing PIN9 stops the sound, but connecting it to the AMP C cable and updating the MCU does nothing.

dudu-lai Yes, but I put it back into the CANBUS harness because I needed sound.

I am using a DUDU7 head unit in a Mazda 6 GJ with BOSE amplifier. I experience a "click/pop" sound in the speakers (especially the center speaker) during device startup and reboot. This issue happens regardless of power or wiring configuration (AMP CTRL wire is stable at 11.2V). I have tried several grounding methods, RCA rewiring and filtering, but the click persists.

I saw on the DUDU forum that some users had similar problems and received a new MCU firmware version which helped eliminate the click/pop.
Could you please help me with that as well?

Here are my MCU/firmware details:

Let me know if you need any additional information. Thank you in advance!