Any ideas?

I’m working on a website in flash (using AS2) and I want to make a portion where logos of companies I have worked for rotate through a masked layer but I just can’t get it to work right. I tried just spacing out tweens with an even number of frames but it’s not working right, no matter how much I try the spacing is never right and it just doesn’t flow. Has anyone else done something similar and if so what approach did you take? Thanks in advance!