If I encode any videos with TMPGEnc 3 and the AC-3 plugin, Sony Vegas 6 will only recognize the video - is there anyway round this? The files play fine in all other programs. Many thanks.

I dont think there are any Authoring programs that recognise AC3 audio. Best thing you can do is to encode the audio to MP2 or leave original when encoding with TMPGEnc and use Vegas 6 to convert it to AC3 when authoring

@asid
I use 2 DVD authoring programs that both recognise AC3 audio. Tmpgenc DVD Author & DVDLab. I use that latter exclusively now as it's much more flexible.

If you're only starting with a non-AC3 audio source then asid's suggestion sounds (pun) fine to me. However, if your video source has AC3 audio it seems rather a shame to lose it. I extract it with virtualdub & then use that in DVDlab to author the final DVD.

Oops! My bad. I made a mistake in my previous post when I said 'authoring' program when I should have said 'Editing' program which is what Vegas 6 is.

If he is trying to open the Video file which has an AC3 audio it cant be opened in an a video editing program. I dont know of any Editing programs that let you edit vido files that have an AC3 audio