Slight shift when reaching a chapter

Hi
I've found a small problem when using chapters with Bsplayer.
I've made a *.bsi file where chapters are declared using frame number:
[chapters1]
1=0 chapitre 1
2=3560 ..
...
10=39500 chapitre 10
11=...

After loading this bsi file, when I want to reach chapter 10 using Bsplayer,
I see pictures just before frame 39500(I don't know which number, it doesn't last very long, less than half a second). The frame number is good because when I ask Bsplayer to reach frame 39500, it goes to the right picture.
This happen with other chapters too.
Could it be a problem of frame rate (I use 25 fps) ?