Sound problem with on board HDMI

Hi everyone. I've been following the youtube channel for a while and decided these forums sounded like a nice place to hang out, so I joined.

I'm currently building a livingroom gaming PC focusing on low noise and so far I've done pretty well, just need to find a good, quiet GPU and I'm done.

My problem is that until I find it I'm trying to use the on board HDMI out on the motherboard (ASRock Z77 Extreme 4) but when I plug it into my receiver I get this high pitched whining sound in my speakers and a sort of scraping noise when I move the mouse.

I'm guessing this is some sort of electrical interference and I'm wondering if anyone else has had this problem before.

Will it go away if I get a separate graphics card?

 

The rest of the specs so far are:

Fractal Design Define R4

Intel Core i5-3570K 3.4GHz Socket 1155

Noctua NH-U12P heatsink

Kingston Beast Series XMP 2x4GB DDR3 1866MHz CL9

 

most likely, the same problem happens sometimes with onboard sound on some motherboards

I have the same problem.... sandy bridge mobile i5

A little update. I spoke a little too soon, it seems. The highpitched sound is only present at the UEFI Setup screen. I haven't attached any drives yet so it didn't get past that. However, I put Xubuntu on a USB stick and booted from that and the sound disappeared, mostly.

There's still some rasping and growling whenever the usb drive is working for some reason. Also when I move the USB-connected mouse around, so I assume the interference is coming from the USB somehow since the ports are right next to the HDMI port.

Thanks for the replies guys, at least I know I didn't damage the motherbord trying to get the power cable connected. :)

tl:dr oh, i don't get any sound at all,