DJM 2000 nexus not connecting to PC correctly

Hi,

Hoping I can solve an issue I have. I connect my DJM 2000 Nexus to my laptop via USB to allow the sound to be recorded and/or streamed to internet radio. I could see the mixer as an input device in the various bits of software. I can no longer see it. It would appear alongside the same list of items found in Sounds>Recoding Devices. I would select the DJM from the list and then the software would take the audio from that input. I do not see the DJM there at all now although Windows is picking the mixer up.

I have changed USB leads, removed and reinstalled the driver, update the firmware to 3.21 (it was 3.20), tried other computers, all the same. When I reinstall the driver and reconnect the mixer I can see Windows installing it and then I am told that the mixer is ready. I can see the mixer in Sounds>Playback Devices, and I can see it in Device Manager. But I cannot get Windows to pick up any sound from it. I am totally stuck and hoping that the soundcard has not gone. What is confusing me is that Windows is clearly seeing the mixer as a device. Could it be that the mixer is not sending some kind of signal to the laptop?

Thanks in advance.