Problems with virtualdub

Hello I’m trying to join 2 avi files using Virtual dub. The process works fine and it does the joining but I get that green screen that covers the beginning of the joined file for about a min. then it disappear. Did any one face that problem before. If so and know the solution I would really appreciate the help. Also I joined 2 other avi files I get the green screen but I also get the sound is a bit off although it is fine in the origional. any hwlp will be great. thanks in advance

What green screen are you talking about ?

A screenshot would be very helpy. Take one and post it, and someone may be able to help (I don’t use VirtualDub very often and never had a problem like yours).