I have just purchased a new HP a6430f computer with a triple core processor, 3 g memory. Running on Windows Vista Home. and have a Realtek HD Audio. I am running CS3 Priemer Pro.
I have captured video no problem. I have played the clips media player. video and sound are ok through the speakers. When I copy the clip from the file to import in the editor. The video plays fine, I can see the sound wave in the audio track but NO sound is comming through.
If Eddie's solution doesn't work for you, and it should, you can also get ASIO4All (freeware www.asio4all.com) and route though it. I'd go with the mfgr's ASIO driver, or the RealTek ASIO drivers first. My suggestion is only for you, should you not be able to do as Eddie suggests.