Clutch noise, intermittent whirring/rattling when disengaged

Hi first time post here. I've searched the forums and cant find something similar to the problem I have. I initially thought my problem was the throw out bearing but the noises coming from my truck are not the same as what people describe for that problem.

When i disengage the clutch (peddle down) I get a loud whirring (don't know the best word to describe the noise). It is not a high pitched chirp and it is intermittent (doesn't happen each time I disengage the clutch). Watch the video please to hear the sound. You can hear me playing with the clutch and gears for a bit then the noise kicks in right when I disengage the clutch one of the times. Changing gears doesn't stop the sound.

https://www.youtube.com/watch?v=DHSgpenuh_w&feature=youtu.be

I can then disengage and change gears and the noise will sometimes go away.

I hope that my problem is unique enough to warrant a new thread but really easy to fix.

Thanks,

Robert