Hi @ben_6960,
Welcome to the Premiere Pro forums and sorry you are experiencing issues. We need a few more details to help like hardware specs. Please see How to Report a Problem.
What type of media are you working with? In the Project panel you can right-click the clip > Media File Properties for more details.
Does this happen with all files and in different projects? Are you getting any errors or do you see any red warning triangles on the bottom right corner? Like Stan mentioned, a scree
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