Realtek HD audio randomly stops working

Hi,
Recently built my first ever computer and everything seemed to be working fine until I noticed the audio wasn't working, so I tried reinstalling the audio driver and that fixed the problem, so I assumed that was that.
But over the last week or so, when I come to load Windows up, I find the audio sometimes working and other times it's not.
It's so random that generally reinstalling the audio driver fixed it but sometimes messing about with settings has fixed it, not sure which. I've even noticed how it fails is random, for example, no audio appears to work, yet the noise you get when you move the audio slider up and down, next to the clock, works fine!
It's driving me mad, any help please?
Thanks

It would really help if you filled in the "My Computer" (specs). Helps us to try and help users.

Hi,
Sorry, didn't notice that, I've done that now

Thanks

Thanks for updating.
The next time you lose audio, check the playback device. It should be "speakers" (Realtek). If its changed to something else, such as HDMI that is the cause of sound loss. If its not the audio playback device, check the Device Manager, Sound video and game controllers section to see if there is any error code showing for the Realtek (report the error code if there is one). If no error rather than reinstall Realtek drivers, uninstall Realtek in the Device Manager but DO NOT uninstall the drivers. Restart the PC and Windows should detect and reinstall the Realtek when it restarts.

Ok I'll do that and let you know the outcome, thanks!