So I have been using this program without problems for a long while now. All of a sudden it’s sucking up 95-100% of my CPU and spikes the temperature very quickly whenever I do anything at all. Also, I can no longer open a file and simply drag it into the timeline. When I do manage to get a video down into the timeline, if I click anywhere along the top bar or rewind or skip back the image freezes and the audio will just continue playing as if I had just let the video keep playing. I change nothing in any settings at all. The program was fine two days ago and now it is completely broken.
You haven’t told us which version or which operating system therefore we can’t help yet.