My Essentials 3tb

I am having problems watching any video from my WD Essentials 3tb. The video is fine when I have it on my computers hard drive, but when I move it to my WD it is very unstable, stops and starts like a DVD that has scratches on it. Any suggestions and what I can do to stop this.

Thanks

Try to heck if this happens with all videos you try to play or only certain file types.

I checked and the videos that I got from P2P sites are playing fine. It is the videos from my cannon camera that are not playing. they were fine a few months ago