I purchased an original iSight after having problems with my USB cam. I just did a clean install of Leopard on my mac pro. The USB cam would get errors in iChat such as "Camera in use by another application, etc). I uninstalled the iChatUSBcam software, checked the Library/quicktime folder, etc. I hooked up the iSight and it seemed to work, then the video went a bit haywire. I thought it was just a glitch, but when I tried to video chat, the other user could not hear my voice. I checked the System pref sound input and it was on the iSight, but the meter was not responding properly. I thought it may be a hardware issue, so I tested the iSight on my mac mini (G4) - It worked perfectly. I have uninstalled iChat and reinstalled it from the Leopard disk. Still no go... After two days, I currently get a good video signal, but am not getting any audio when hooked up to any port on my mac pro, but it works perfectly on the mac mini, so I am still convinced that this is a some sort of driver of software conflict Any Advice?