Transitions not rendering properly

I'm on DVR 20, and I'm having an issue with some of my transitions not rendering properly, even though they work fine when I play them in the timeline. Any ideas?

Dude, that's the equivalent of calling an auto shop and saying "My car doesn't work. Why?"

You give us NO information to go on here.

Why the hostility? I think what I said is pretty clear. I put some transitions on some clips, and they work great when I'm watching in the timeline, but when I render the project, they are different. They are crap. They are glitchy. Is that enough info?