Adobe premier pro problem

[vedant321]

hey guys i m using premier pro cs 5.5 the problem is whenever i edit a video with some added audio like for eg-the other day i was tryin to add a song to a clip of a movie so when i try to export that video the video size becomes smaller and when i export the video of a movie with its original audio only the size is better
guys plzz help

 

[jamesmcuk]

Actual video picture size or length of playback?

 

[kenrivers]

Are the export settings the same for both clips (with and without added music)? Are the sequence settings the same for both clips? When you export, what format are you using (H.264, .AVI, MPEG2)?