Radeon 4650 Bitstream Out Support?

I'm running into a bit of a peculiar problem when I attempt to output either Dolby Surround or DTS (any flavor, DTS-HD Master Audio or DTS 5.1). I've been utilizing a 3rd party codec to allow bitstream output via HDMI passthrough of both AC3 and DTS (ffdshow Audio Processor). However, whenever I enable the DTS passthrough, the sound cuts out. If I'm in my receiver's (Yamaha RX-V565) OSD at the time, the signal will display all the correct data (number of channels, bitrate, etc...) but it will be pulsing rapidly. Meanwhile, the LED read-out on the device will pulse "DTS" at the same rate.

My inquiry is into whether anyone knows if the 4650 can even output DTS in bitstream form over HDMI Audio. If so, then it's obvious I have a simple configuration problem, and will continue to poke around until I solve it. However, the rapid-fire pulsing makes me believe that the card doesn't support it. Which then leads me to the question regarding the fact that all the data populates correctly.

Advice, anyone?

So, indeed. I discovered that upon uninstalling and reinstalling the K-Lite codec pack (x86 instead of x64), AC3Filter is installed. As soon as I specified the passthrough using this rather than FFDShow Audio Processor (kudos to the suggestion for Shark007, as when I looked through it I noticed it had AC3Filter), it passes through perfectly. Thanks for the assistance!