Hi @attila,
thank you very much for your very quick and detailed reply! I'll try to find a similar one.
I have just tried the original cable again, but with that one it doesn't work at all anymore, the device it is not recognized at all, even if I move the connector a bit. With another no-name cable which I'm using, it's recognized successfully in Waveforms, but as soon as I move the connector a little bit, the connection is lost.