Video backgrounds for songs in Stepmania

[FirstClass]

I've downloaded a song which has a still image background. I am trying to add a video to it but I am having some some problems getting it to sync. I manually added the video by editing the sm file in notepad. The video starts playing as the song starts but a few seconds later it replays again throwing it completely off sync. I've checked the step file inside the editor but theres nothing hinting the rewind of the movie a few seconds after the song starts.

Any ideas?

This is the header of the sm file...

#TITLE:Chung Hwa Ban Jeom;
#SUBTITLE:;
#ARTIST:Louis;
#TITLETRANSLIT:;
#SUBTITLETRANSLIT:;
#ARTISTTRANSLIT:;
#CREDIT:;
#BANNER:Chung Hwa Ban Jeom.PNG;
#BACKGROUND:Chung Hwa Ban Jeom.avi;
#LYRICSPATH:;
#CDTITLE:;
#MUSIC:Chung Hwa Ban Jeom.MP3;
#OFFSET:-8.330;
#SAMPLESTART:46.754;
#SAMPLELENGTH:12.000;
#SELECTABLE:YES;
#BPMS:0.000=149.500;
#STOPS:;
#BGCHANGES:-8.330=Chung Hwa Ban Jeom.avi=0.700=1=1=1,
222.000=Chung Hwa Ban Jeom-bg.png=1.000=0=0=1,
99999=-nosongbg-=1.000=0=0=0 // don't automatically add -songbackground-