Does this happen from a file on the Web or a File on your Computer? You probably can't fix it if it is on the Web and doesn't happen with Files on your Computer, but if it is on your Computer you can try cleaning up your Processes. Ctrl Alt Dlt will show you them... see which ones you don't need, always worth a short. Or clean out your Task Bar. Something like that shouldn't happen if you Computer is less than two years old and not doing much else.
Beyond that... I don't know. I suppose it also depends on the length, if it is on your Computer and it is 5 hours long, and you're jumping an hour, you'll have to expect that whatever you do!