Clip compatibility problem after installing on new computer

[flyingbeatle]

My HP Slimline fried itself (didn't know it was recalled two years ago and HP's "solution" was hardly adequate but that's a whole other story)

waited for Windows 7 to come out and bought another HP, this time a quad core desktop which I know is capable of handling Video Studio (which worked just fine on the Slimline)

I installed VideoStudio Pro X2 but on my first attempt at putting clips on the timeline, here's what happened:

Put Clip B on the first track, then Clip A as an overlay on the second track. When rendered together Clip A becomes extremely corrupted (pixellated).

Tried putting Put Clip A on first track, then Clip B on the first track after it. Same problem occurs with Clip A.

Tried Clip A all by itself and it rendered fine. It's when I try to use them both in the same project, Clip B works but Clip A becomes corrupted.

I checked the field order in case that was the problem, but both clips are mpeg2 video, upper field first.

Then I got imaginative and added a track, and put Clip B on the second track and Clip A as an overlay on the third track, leaving the first track empty. This worked upon rendering -- but it took a lot longer to render.

So does anyone have any suggestion what the problem might be, or why the first track would be treating one clip as incompatible or whatever is going on? I tried two other entirely different clips along with Clip A and the problem did not occur, so what is Clip B "doing" to Clip A? thanks for any help

[Black Lab]

Can you please post the properties of both clips, the properties of your project, as well as your output properties?

[sjj1805]

On the limited information available my best guess is that the height / width of clip B is larger than the height / width of Clip A
And / Or clip A has a much lower Bit Rate.