Video plays in slightly fast motion -XP Pro 64BiT i7-2600

[ReViZeD]

video studio pro x5 ultimate - problem is either
1) the audio is not in sync
2) and now this new problem the video plays in fast motion
the main mission of ReViZeD will always be , all videos are usually xvid with intentions to edit scenes and create video to xvid "with same or slightly less video quality but most importantly with sound in sync" and i always use video inspector to try and keep the files as close to the original as possible.

original file
576x432------------->576x544
fps :25 --------------> i have tried 25, and 29.97(never tried any others)
bitrate 1475 --------> i always add 30%
quality factor 0.24b/px - i have no idea what this is or how to adjust its outcome?
codec xvid mpeg-4 ------->same
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audio
channels: 1--------------------------------------> i usually chose stereo the highest stereo setting, 640k ac3 always worked before
sample rate 48000 hz ------------> always chose same
bitrate: 94kbps -------------> always chose highest possible
codec: mpeg 1 or 2 audio layer 3 mp3 --------> i dont know what the difference is between mpeg layer 3 and mpeg audio layer 3? although i have tried all audio settings with same results
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i created these files before with no issue , by (in audio clicked advanced then clicked interleave audio/video every "1" frames) what i usually do to work around the many other issues video studio has given (out of sync audio) me is not working now with regards to producing the video in a mickey mouse fashion. in the past if a video would not have audio sync i would render the file with no edits using ac3 audio first then edit the created file with no change in the video settings"always worked" ( and now for some reason every now and then when i chose ac3 i get this error "unable to access codec driver" even if i get it to create with ac3 or mpeg audio(never a problem chosing mpeg audio) the program will freeze at 99% (never had this problem in 5 years until i started using x5) and i have kinda worked around this by ending process tree and then using virtualdub to repair the xvid and i end up with the same results ,a video that plays slightly fast motion.

i have found out that i only have the problem of out of sync audio if i am dealing with a video that doesn't have ac-3 audio originally. i have 3 of these files and the first one worked. audio was barley out of sync that it doesnt bother much. tried videostudio 11.5 with same results