Another NK3m going dead

First of all, thanks for such a feature-rich and convenient device. When it works, it’s great.

But there’s some troubles with my one out of the box (2nd day of using). When inserting into any USB socket, its behavior may vary:

  • blinks different colors, detecting by the system, ok
  • blinks, but not detecting (device descriptor read/64, error -32)
  • red+smth else glows, not flashing, not detecting at all
  • brick, nothing happens

When it jist in place and works, it may suddenly disappear from the system: ccid_usb.c:961:WriteUSB() write failed (1/7): LIBUSB_ERROR_PIPE. Or it may works ok for hours:

% nitropy nk3 test
Command line tool to interact with Nitrokey devices 0.4.47
Found 1 Nitrokey 3 device(s):
- Nitrokey 3 at /dev/hidraw0

Running tests for Nitrokey 3 at /dev/hidraw0

[1/5]	uuid     	UUID query              	SUCCESS  	DAD2B981D2792A960000000000000000
[2/5]	version  	Firmware version query  	SUCCESS  	v1.7.0
[3/5]	status   	Device status           	SUCCESS  	Status(init_status=<InitStatus: 0>, ifs_blocks=233, efs_blocks=462, variant=<Variant.NRF52: 2>)
Running SE050 test: |                                                                                         
[4/5]	se050    	SE050                   	SUCCESS  	SE050 firmware version: 3.1.1 - 1.11, (persistent: (26576,), transient_deselect: (607,), transient_reset: (592,))
Please press the touch button on the device ...
Please press the touch button on the device ...
[5/5]	fido2    	FIDO2                   	SUCCESS  	

5 tests, 5 successful, 0 skipped, 0 failed

Summary: 1 device(s) tested, 1 successful, 0 failed

I noticed a little micro-movement of NK in the socket may results vary - it could broke a working case, or could fix r/w errors. Reseat of device is also helps in some cases. Touching the device could produce its inaccessibility. So I just cant use such an unreliable token.

Tested on 4 different laptops in all of USB they have.

Looks like there’s a buggy contact somewere inside the NK.

And the question is - what should I do next? I’d like to replace it on smth more reliable, maybe, full-size USB keys are not so buggy. I’m afraid this NK3m will finally dead some lucky day, maybe even tomorrow.