That's exactly where I went wrong. The Alto USB out is affected by the main mixer slider. With that on zero nothing was being sent to the PC. Now I have that working. I would never have got this without your help. Strange the different working with the Wharfdale. That one the USB out is only affected by the channel input where the mic is and even the main mix pot on zero. The USB from the mixer seems to be at a preset and not affected by the main mixer pot. Anyway now I can start experimenting with the Alto and learning more. Apologies for being so convinced it was faulty. Good lesson learned. Thanks and take care. Bryan.