My PC has started making a loud buzzing sound mostly when I watch vids on vimeo but has now started when I put youtube vids on.
It does go stop after I click off the video but does anyone know what is causing it.
Answers in plain english please as I am a numpty when it comes to computer talk.
Thanks Rob.

PC fan. Chances are that your PC is mostly idling in terms of use and when you're watching "artistic" videos, the CPU is working harder and needs more cooling. If you're a hopeless numpty where PCs are concerned, either find a suitable person to swap it (or grease the bearing if they're feeling up to it) or pay a shop.

The fan.

Thanks peeps I will get it checked out.