Material UV distortion becoming worse after time.

So I’ve been making some rather simple shaders for a little side-project of mine, this shader is specific is a translucent caustics shader that is applied to a plane and placed above my water surface. When applying the material to the mesh in the editor the UV distortion looks all kinds of wrong, however it works perfectly fine when in-game, that is for a few minutes! I noticed last night that the UV distortion is actually becoming worse and worse by time untill it reaches the point where it’s identical to the distortion seen in the editor window, what on earth am I doing to cause this?

Here is an image showcasing my my problem and my material set up.

https://dl.dropboxusercontent.com/u/63462053/UE4Help.png