I am using my computer as HTPC (Home Theater Personal Computer) connected to my TV and my reciever. I run Microsoft Windows XP Pro SP2 with all the most recent updates. The problems comes with digital out on my Chaintech AV-710 sound card. I have the card installed in my PC correctly, and I have tried both PCI slots. IT is fully seated and secured. I installed driver 1.43d and did a reboot. I then set it up to enable digital out to my reciever. I have tried both optical ports on my reciever, and 3 differant optical cables. I was able to confirm both ports on the reciever and all 3 cables work with a differant component (DVD player). Now when ever I try to play anything I get no sound at all. I have tried with Cyberlink PowerDVD playing a DVD and I have set it to use spdif I have also tried using ac3filter and setting it to spdif And I can confirm the file I am playing is using ac3filter for sound Im not sure if I am missing a step or have a setting wrong, please let me know. Also when I connect regular computer speakers to the line out I just get a high pitched solid tone. I am thinking I just have a bad card that I need to RMA but want to make sure prior to doing that.