Thought it must be down to the USB device so started looking for a pci card to use, I was very lucky and found a brand new saa7134 4 chip card on ebay for £28 this included DHL shipping so that i got my card 2 days after ordering (not 10+ days, normal for China to UK)
From what I can tell the card is 8 channels as I can select (0) and (1) on each of the 4 /dev/videoX but the lead supplied has only 4 video channels and 4 audio channels.
h x x p : / / stores ebay com au / cctvdiscover (look for pci cards) has 9404 printed on the card.
I made them an offer of $50 (AU) and it was accepted
I may have been very lucky to get it at that price but I did so I am happy.Thanks also for the Wiki that helped me to setup the card.