If you`re using a laptop, Ill assume this is a usb device. I don`t know if things have changed with usb2.0, but with a usb1.x tv tuner the picture will not be sync with the action, I guess cuz it takes extra time and/or cpu power to pipe stuff through the usb bus as opposed to a pci device. Don`t know if this applies for you in this case, but thought you might appreciate the warning