Controller (maybe) not recognised by Laptop

Hello, I have recently bought your U-Mix Control product and am having trouble setting it up with my laptop. I have had it working but not consistently.
If I plug it into the laptop & turn it on all of the controller lights light up once & the only light that stays on is the orange power light. If I then start the Cross DJ software that opens up okay but moving any comtrol on the controller does not move any control on the software screen and no further lights light up on the controller and no music plays out.
I have checked & the U-Mix Control Pro is listed as default sound device on the laptop.
I have had the set-up working but last time it took me 90 minutes of opening & closing Cross DJ & turning on & off the controller & plugging in & out the USB.
By the way I have updated to the current (1.7.1) software.
Thanks in advance!
If I plug it into the laptop & turn it on all of the controller lights light up once & the only light that stays on is the orange power light. If I then start the Cross DJ software that opens up okay but moving any comtrol on the controller does not move any control on the software screen and no further lights light up on the controller and no music plays out.
I have checked & the U-Mix Control Pro is listed as default sound device on the laptop.
I have had the set-up working but last time it took me 90 minutes of opening & closing Cross DJ & turning on & off the controller & plugging in & out the USB.
By the way I have updated to the current (1.7.1) software.
Thanks in advance!