Took me 1min to search google for "DTS,AC3 audio codec" search a few of the links and find this [External URL submitted by user - Login required]
Just download and install.Then follow the first step and click that "All Disable" then click "External Audio Decoder" then click on "External Decoder Search".On the right of the new poped window pick AC3 and DTS ,after that just click "add after scan" . Then close the External Decoder/Filter Managment.Then for AC3 and DTS audio either pick "system defaulth" or "ac3filter".In the end should look something like this.