i just converted a very merry pooh year ac3 to dvd-r - it came out perfect. load the avi into virtualdub, set the audio to direct stream copy not full processing mode, save the wav. Rename the wav to xxxx.ac3 then use ac3fix.exe to fix any errors, then use HeadAC3he to convert it to a .wav, after that u convert it to a dvd mpeg in tmpgenc then author it with ulead dvd workshop or whatever. This definitely worked for me