@milaidin :
Poking around in the schematic shows that the Audio jack has a switch pin connected to a line labelled HP_DET on the board. As far as I can tell this line is pulled low via R47&R48 unless there is a plug inserted. when it is pulled high via R49 instead.
This HP_DET line does not go directly to the P4 chip, instead it goes to U6, which is a I2C I/O expander chip on the system I2C bus.

If the source for the demo is available look for how this line is read, then turn the amplifier on/off as needed. The code for that should also be in the demo.

Hi @MortenComadan ; you don't mention what your project is based on for code; Arduino/ESP-IDF/MicroPython/UFlow2 etc..

For the tools where Expressif have got involved the support should be there already. The C6 co-processor gets a standard firmware (that talks via QSPI to the P4) and the P4 IDF libraries know how to use this.

• What I'm unsure about is exactly which features are actually implemented in the ESP IDF; I want to use bluetooth audio sink features.. eventually.

If (like me) you are into MicroPython then good news. V1.27.0 was released a couple of days ago and has official P4 support: https://github.com/micropython/micropython/releases/tag/v1.27.0

UFlow2 is based on an older micropython version; I'm not sure how much of the P4 stuff they may have backported.

I only got my Tab5 today, I'm going to be installing micropython 1.27 asap.