i2c broken?

Hi,

I bought a NyBoard version 1.0 in March 2021. It was meant to replace a working DIY board to be more stable than the breadboard approach.

Sadly, it never worked - I narrowed down the problem to be i2c related, I think. After retrying the whole thing again some days ago I found out that the Arduino/RPi switch is broken (cover is loose and thus the connection in either setting does not work). I worked around the problem by soldering the connection to Arduino. However, it still does not work.

"Does not work" means, I upload the i2c example sketch via Arduino and it gets stuck at scanning (never finishes the scan). The same sketch on myy DIY installation works like it should, reporting the i2c adresses of MPU, EEPROM and Servo driver after half a minute or so and stops.

The board is powered up, both LEDs light up. Everything else works, if I upload the Nybble sketches, it beeps (so Arduino and Pins are working), but never finds the MPU.

Any idea how to get the board running? I desoldered the IR LED as I needed one for another project (and was annoyed by Nyble not working) but that should not interfere with i2c? Even if I try to access i2c with an external Arduino (switching to RPi and connecting i2c to external Arduino) it shows the same behaviour.

Thank you and with best regards

Stephan