VideoStudio :: Jump / Stutter In Finished Video - X5 Ultimate

I have just put together a 20min video and have several times created an mpeg file on the hard drive as I edit different parts, so that I can see how it comes along on a main TV thats networked to my PC. The footage is from two Panasonic HD cameras and is filmed in AVCHD.

The last two copies I have rendered have 4 scenes with noticeable jumps/stutter. They are all taken from and are part of a clip 146, the music track dosent jump, just certain parts of the scene in the video. This jumping is intermittent in about 30 seconds and the rest of the 20min film is fine. No filters or adjustments have been made to these scenes and they were fine up until yesterday. I tried a second render but its the same.

I would like to know what causes it so I can either avoid this happening again or avoid VS altogether as I have put in a lot of time and work into this 20min video and I don't want to have to do it again, I really want something I can rely on. I have had VS from the very earliest version and I have found that these bugs keep cropping up.

UPDATE:I have done further tests and it is ok if I "Create Video file" Same as Project Settings" BUT if I "Create Video file" DVD Video" it stutters/jumps. I have attached the properties of the scene now.

Most of the footage is Panasonic AVCHD and I use Two Pass Encode. Am I using the correct settings for this type of film. I want to film in the highest quality so that I can copy to blue ray and standard DVD.

My project settings are:

Two Pass Encode
PAL (25 fps)
MPEG files
24 bits, 720 x 576, 25 fps
Upper Field First
(DVD-PAL), 16:9
Video data rate: Variable (Max. 8264 kbps)
LPCM Audio, 48000 Hz, Stereo

The DVD settings are:

MPEG files
24 bits, 720 x 576, 25 fps
Upper Field First
(DVD-PAL), 16:9
Video data rate: Variable (Max. 8000 kbps)
Audio data rate: 384 kbps
Dolby Digital Audio, 48 KHz, 3/2(L,C,R,SL,SR)