wlmp timing discrepencies

Hello All

I am getting really frustrated with wlmp. This is the first time that I have used wlmp. All my other projects were on wmm. I like wlmp a lot. but..... I notice a difference between the preview window timing and the full screen preview. It's minuscule. But its enough to throw off what I am striving for in timing. Any ideas on what I can do?

I have edited and re-edited the timing of the frames to no avail. What works on the big preview does not work in th small oreview. And vice versa