Mixing 16:9 and 4:3 Assets in a Track
Keep in mind that a track’s aspect ratio setting applies to the entire track. If you mix 16:9
assets with 4:3 assets in a track, you will have problems when playing it back. For example,
if you set the aspect ratio to 16:9 Letterbox, the 4:3 video will also be letterboxed and
end up looking vertically compressed.
To be safe, do not mix 16:9 and 4:3 assets in the same track. Instead, create separate tracks
for each. You can use the Connections tab in DVD Studio Pro to control the playback
order of the tracks.