Apologies up front for a lengthy post, but I have tried to include answers to a host of questions that I would assume would emerge if I just presented the problem itself.

I have been using MTR and Toast in combination for various types of burning for a few years and on my iMac Intel 10.5.8 for about a year. I have been using MTR 3.0 14m and toast 10.0.2 with no problems beyond one slight quirk with Toast crashing (solved via help on this forum and a software re-install). But now I am having a strange problem whenever I use Toast to burn VOBs or MPG files in the Video Tab setting. When I watch the burned DVD on either of my set-top players (both of which have played these DVDs fine for the past couple years) the image is jumpy; it looks like a PAL>NTSC conversion or as if the DVD was copied form a macrovision protected source--neither of which is the case here. When I play the DVD on my computer, everything is fine; it plays as smoothly as all my DVDs used to on my set-top players. I have recently noticed this problem (last week or so) but thought it had to do with muxing (more on that below and discussed in another thread) so the problem is recent. I have also updated Toast to 10.0.6 and the same problem persists. I have done a cold re-start on my computer both before and after the Toast update and that did not solve the problem.

Here is some more background information that may or may not help:

1. I have burned using my Pioneer external drive connected via firewire and I have burned using the internal drive. There is no difference;the image is jumpy.
2. If I do a straight copy of my original DVD using Toast on the external or internal drive. The DVD plays fine on my set-top players.
3. If I do a full disc extraction with MTR, and burn using the data tab setting in Toast, the DVD plays fine on my set-top players.
4. If I drag and drop the VIDEO_TS folder to the desktop and burn that folder in Toast's data setting, the DVD plays fine on my set-top players.
5. If I do a full disc copy with Disk Utility, the DVD plays fine on my set-top players.
6. I have this problem with a jumpy image whenever I use the Video Tab setting on Toast and am burning files that were extracted as individual Title Chapters using MTR. This includes (A) NTSC files extracted from a DVD that I recorded from my Toshiba set-top DVD recorder (I needed to do this because the recording was out of order due to a screw up with my DVR), (B) NTSC video m2v files that were created using MPEGstreamclip and MpegWorks from VOB files extracted with MTR and then muxed with new audio, and (C) PAL video muxed with new audio (using the same process as the NTSC mux).
7. The problem is not media specific. The image is jumpy on my set-top players when using Verbatim DVD-R and TDK DVD-R. And I always burn at 4X.
8. My video tab settings in Toast are set to Custom with Video: MPEG2, 4.0MBPS (8.0 mbps max), reencode never, 4:3; Audio is Dolby Digital 448KPS. I have had this same setting since I was using Toast 7.

As I noted at the beginning, this is a strange quirk because I have burned individual VOB or MPEG files in Toast that originated from DVDs using MTR hundreds of times and never had a problem. Plus the images play fine on the computer without any kind of problems with jumpiness. Is there (A) something that might have happened with an Apple software update that could produce this problem or (B) some setting in either Toast or MTR that I might have accidentally checked that is causing this problem?

Finally, I do not know if Disk Utility can burn individual VOB or MPEG files (it does not appear to) so I haven't been able to test another burning option.

Thanks for reading this lengthy post.