Hi ostepan2006 ,
That's not good to hear. Could you shoot an email to firstname.lastname@example.org on that? We can get you a replacement out to you and then a return label back for your device so we can see what is going wrong.
Also, so one note on this: If you're switching back/froth between Gen1 and Gen2 examples, you will need to unplug the OAK-D from USB and power. Otherwise it will be unresponsive and make on think that it's not working. But rather it's just there waiting for the wrong library to talk to it.
So could you give this a shot first if you haven't already?