inconsistant audio bitrate

hmmm as the subject says wen i put my m2v file into spruce up it then sucks the ac3 file along with but after its loaded it it says inconsitant audio bitrate and drops the sound file the movie im trying 2 backup is pearl harbour has anyone got any ides on how 2 fix the ac3 file so i works but i still want 2 keep the 5.1 propertes ??

You must rip off the trailer at the beginning.

there is no trailer at the start or anywhere else in the movie

Logo or trailer or end credits.. 

These can cause the probs..... Use powerDVD .....and enable the info on the clip ...u get the video & audio bit rates.......dvd2avi wil also give the audio type. use Power dvd to browse the beginning VOB and the end VOB ....to find out where the audio changes..... Use VOBedit or Vob split to cut out the bad part.