Animated Texture Sampler

There is an undesired behavior when I create a shader trying to sample a texture at a specific UV coordinate where at least one axis is animated.

This setup creates an UV coordinate in every tick sampling at the current position in the texture according to the time.

This is the texture.

Howeever. If I close Shader Forge and press Play in Unity it starts blinking as intended.
If I reopen Shader forge the Shader displays correctly for a while and stops to display the correct behavior after a short amount of time.

I created the same setup in a Code-node and it gave me the same result.