AC3Filter and AC3File are two different things. File allows you to play DTS and AC3 files via Directshow (ie. in WMP and MP) where as Filter does many things like decoding, encoding, mixing....
The other option is that your default DTS decoder is not set to SPDIF passthrough.
To debug download graphstudio (32 bit even on 64 bit os). Then click the render media file option and chose one of the DTS files. This will show you what decoder is being used.
The other option is that your default DTS decoder is not set to SPDIF passthrough.
To debug download graphstudio (32 bit even on 64 bit os). Then click the render media file option and chose one of the DTS files. This will show you what decoder is being used.