I followed g3gg0 howto “Toniebox Bluetooth Modification” and implemented the mod by myself meanwhile with the “KCX_BT_EMITTER”.
It’s working pretty nicely, but I would like to share a finding I had during the HW implementation on the board.
I’ve got the ESP32 Toniebox HW/PCB which is the very recent version that has the vias covered with that ugly silkscreen. I managed to remove the silkscreen very very carefully with a flat and sharp screwdriver.
Implementing the headset detection with Si2302 mosfet as described, I realized my Toniebox always hung up in headset mode after start up of Toniebox. It then returned smoothly to speaker mode when the BT headset connected and disconnected again. So I assumed it’s an improper start-up behavior and I discovered the LINK output of the “KCX_BT_EMITTER” board was floating around too long during startup phase that put Toniebox in headset mode right away.
I could solve the issue by adding a 10k pull-down resistor directly at the LINK output to GND at the board terminals. Now my Toniebox starts up properly in speaker mode until a BT headset is connected.
Cheers, Paul