When exporting to DVD, random problems with Alpha channel
I created some lower-third graphics in After Effects and rendered as “Lossless with Alpha” Quicktime files. I imported them to Premiere Pro 1.5 and put them in a video layer above my DV footage in the timeline. When I press spacebar to play the sequence, everything looks fine (ie. the graphics are overlaid on top of the video with the alpha channel being transparent.). I have a 13-minute video sequence, so I have a graphic come on then wipe off. Then another graphic comes on later then wipes off and so on.
But when I export to DVD, sometimes everything looks fine, other times the graphic comes on with the alpha channel black instead of transparent blocking out the video behind it. I use exactly the same technique throughout the video sequence. I have tried encoding with different bitrates but to no avail. It seems random. One time I burn to DVD and the problem occurs in one part of the video, another time I burn and the problem occurs in a different part of the video but the first part is fine again. Is this a glitch with the Premiere Pro software? What do I do to fix it?