If you are able to install your driver, open the control panel and change frequencies, but not able to detect the ScratchAmp2 in FinalScratch or select it under Windows sound manager (Control Panel > Sounds and Audio Devices > Audio), chances are that you are running Windows XP Service Pack 2 which has a known issue regarding 1394 speed. Service Pack 2 implemented some changes in the FireWire (1394) host drivers which can actually slow down their performance and allow the ScratchAmp2 to be recognized by the system but not actually pass audio.
To determine if you have SP2 installed
To determine if SP2 is installed on your computer, follow the below steps:
1) Click Start > Control Panel.
2) Double click on “System”
3) Under “General” you should see the version of Windows that is installed on your PC. If it reads “Service Pack 2”, then it is suggested that you taking the following steps below:
Installing Microsoft 1394 hot fix
To install the hot fix for
the 1394 driver follow the directions listed at the Microsoft knowledge base