Beeping PC

I have a problem with my new toaster namely it beeps. At first I thought it was PSU (EVGA NEX750B) tested on old pc, no problem there. Then it was suggested it might be coil whine on my GPU (ASUS R9 290x DirectCU II), no such thing tested with old GPU sound still persisted. I got around to mobo and in the end replaced it with GIGABYTE 970A-DS3P. I had a thread on here about mobo https://forum.teksyndicate.com/t/msi-970-gaming-mobo-beeping-dives-me-crzy/82239/35
I disconnected everything that wasn't on mobo to eliminate variables, sound was still there.

Any ideas how or why it happens and how to mend it?
One more thing it might be irrelevant but when I scroll big pictures in firefox the sound acts up.

computer beeps are the result of it trying to communicate errors that it cannot display for whatever reason. Just look up that specific error code and see what it means.

what version of windows are you using? if its 8.1 i would give this a look. http://toastymallows.com/fix-scrolling-too-fast-causes-windows-8-dot-1-to-beep/

No, I'm on windows 10. And was on 7 at the time.
Thanks anyway.

Is the issue allready solved or not?

No, I think it has something to do with the power in the house. I remember that something to lesser extend happen with my old machine after I moved here. It is an old house...

You might be able to solve it with a UPS they don't just keep the computer running in power outs but clean the power before distributing it to your machines.