sorry but you cant get ac3 audio with rca cables.you will need the optical cable to get ac3 then be hooked up to some surround sound system. i have also heard you can buy a ac3 decoder box but im not familiar with that device. hope that helps and yes i am getting ac3 sound with the optical cord with the vs9000hd.
it wont be ac-3 audio but you will get sound through the RCA cables on a ac-3 channel. All of the HD receivers have this feature. No extra equipment needed