I have a multiplexed .VOB file that is playable by a DVD player (assuming all the menus etc are present). When I burn this to DVD using the Toast "DVD-Video" option (in the side panel), Toast begins to multiplex this file which takes a fair while on my 600MHz G3. I've checked under Edit (in the Toast window) to see what sort of file Toast thinks it is and sure enough, Toast tells me it is a multiplexed file (this is before burning), then it proceeds to multiplex the file. The burnt DVD works OK.

Why does Toast do this? Is it technically necessary to re-multiplex a functional multiplexed .VOB file?

First thing, update Toast to 6.1.1. Next, do you intend to burn the Video_TS as it or do you intend to re-author the content?

I'm just experimenting at the moment, playing around to see how these things work. I won't be reauthoring the .vob file. I'm just intrigued as to why Toast re-multiplexes a multiplexed file. Is anything changed by doing that? Will upgrading to 6.1.1 stop Toast re-multiplexing?

Files most be multi-plexed. All multiplexer are different, and if they are not re-multiplexed, the menus, time codes extra can't be generated. Also, VOB have extra data like multiple audio tracks, subtitles, etc. This most be stripped to burn, unless using the re-compression function of Toast.

I have a similar problem, where I prepare a vob including subtitles, and they are stipped in the re-encoding process. Is there a way to retain the subtitles when using source VOB files which have subtitle tracks present?

Many thanks, ja9ae.