I cant find an answer to my problem and I am not sure what I am doing wrong. I have 2 avi clips, one made by capturing the screen whilst zooming in on google earth and another made by a program that creates a screen capture of the program itself. I have used virtualdub to modify the google earth avi and it is now what I want. When I try to append the second avi to it, I get a sampling rate error - the first has a rate of 33.33333 and the second 50. I got hold of virtualdubmod as it was supposed to allow the append to take place. But I get the same error in virtualdubmod. There is no audio on either avi. Can I change the sampling rate on one of the avis? If so, how can I do it? What effect will changing the sampling rate of an avi have on it? I would appreciate help as this is driving me nuts.