What are your PC's specs: GPU/CPU?
Where are you seeing this - in preview or after export.
What version of VP is being used? Try the latest. For licensed users upgrades are free for up to six months from purchase date. After that, VP will continue to fully function but a fee will be required in order to register the newest. Retain your old install file and registration info.
If that doesn't help, go to OPTIONS | ADVANCED tab and in the GPU processor area at the bottom, choose None (CPU only) from the drop-down menu.
Please report back which measure, if any, succeeded.
