Windows 7 Sound randomly cuts out!

[Luigi Severis]

Since April, whenever I have viewed media like Vines (6 second web videos) or listened to music online (various sites) my sound has completley cut out and I have had to restart my computer because of it, it also affects YouTube videos, they give me an error message. I am using Mozilla FireFox with Shockwave Flash.

 

[Pauli]

The shortcut would be to check that you have the latest of FireFox and Shockwave. If music and video CDs and DVDs play well, the cause is somewhere along that line.

The error message would be important to see, as a screenshot or something.