When I load a certain AVI, it says "VirtualDub has detected an improper VBR audio encoding in the source AVI file and will rewrite the audio header with standard CBR values during processing for better compatibility. This may introduce up to 55442 ms of skew from the video stream. If this is unacceptable, decompress the *entire* audio stream to an uncompressed WAV file and recompress with a constant bitrate encoder. (bitrate: 113.3 ± 16.3 kbps)". When I try to divide the AVI in two, the audio isn't in sync with the video. How should I fix this?