In order to allow you to fit more video on to a DVD use A-Pack to re-encode the audio to AC3 format. This reduces the file size for audio and means you can fit more video on to the disc.
Settings to Use for Encoding AC3 Files with A-Pack
- Audio Coding Mode : 2/0 (L.R)
- Data Rate : 192 kps
- Dialog Normalization : -31 dBFS

- Now click on the preprocessing tab and set the compressions setting to ‘NONE’.
- Click Encode and choose a file name and location.

The final step is to locate your aiff audio file and drag and drop it into the left input channel if it is a stereo file, you will be prompted to make it the LEFT Channel and the same happens when you drag the same file to the right input channel, except this time make it the RIGHT Channel.
The AC3 file is approxinately 8 times smaller than the aiff file.