up2stream2.1 turn-on-thump [solved]

Hi there,

I just wired up my 3rd up2stream2.1 board and got surprised with a huge “plop” in the speakers everytime I connect the battery to the device.

I know them plopping slightly when disconnect power, but on connecting power my other 2 boards make no sound until some content is being played or the internal voice is telling me “connected to your wifi network”

Its the only board that does this loud sound while switching on.

I forced updating the device via API command and its now on latest alpha from raokit.
I did factory reset before and after the update.
No change of that plopping behavior.

May I have a faulty board?
On visual inspection the board looks fine.


Thanks for nothing but I share the solution anyway.

I spotted an additional 10k resistor on my good working boards which the newer boards dont have.

Adding this and popping is gone.