Video scrubbing in latest photoshop non beta can only scrubb forward not backwards?

Hi, I'm using tha latest version of photoshop I.E. non beta and for some reason, the video scrubbing with the time head seems to allow me to scrub forward but not backwards? If I try to do the same thing using the photoshop beta I don't encounter said problem?

Hope you are able to understand and Thanks for your help 🙂