Hello :)

I have based a custom board on the Nano 33 BLE. Because the NINA-B306-00B is sold out, I would like to use the NINA-B306-01B (which is identical and only misses the external crystal). I have soldered it onto my PCB and flashed the bootloader.bin frome here onto it via SWD using a jlink. I can see the device showing up in the Arduino IDE when I put it in DFU mode (press RESET twice) and also loaded sketches onto it in that state. However, it appears that something is going wrong as after flashing, the device does not show up on my list of USB devices and also it appears that the sketch is not running correctly on the Arduino (e.g., a simple LED blinky example does not work).
I can not flash the device outside DFU mode as it is not showing up in the list of devices.

From my understanding, the only difference between the two modules is the 32.768 kHz crystal. Is that causing a breaking change in the software? I was thinking that the missing crystal will only cause some timing issues or so? Do I need a different bootloader to account for the different crystal (e.g., to avoid having bad Arduino delay() accuracy).

So it appears that some additional changes are required to make the the NINA-B306-01B compatible? Any help would be greatly appreciated. Thank you very much!

Thanks,
Tobias