I've been using my KryoFlux successfully, on and off, for a number of years. Just recently though it started to not function as shown in this short video clip:
That is running "dtc -c2" on a Windows 10 machine, and I get the same on a Windows 10 VM on macOS. The floppy drive is a Sony MPF920 which has worked perfectly before, and I have also tried a second floppy drive with the same results.
I'd appreciate any suggestions what the problem might be
Could also be the track zero sensor not being recognized! I would check for dust on the sensor first. If that doesn't solve it, I would try a different cable...
I agree with ZrX in that the printing on the screen would be much more helpful than the video in this case!