I'm using Toast 7, trying to burn some AVI files to DVD. Each file is roughly 350MB, there are 6 files, so roughly 3.5GB of video. However, when I add them all in Toast and go to burn, I get a message saying the inserted DVD can only hold 4.38GB, and there are 8GB+ to be burned. Is there a reason why such small files are causing me such big problems?