Strange Buzzing sound coming from Green Line out.

[PokeyUp]

Hi LTT Forums. I've got a most likely simple question I think you all could help me with. So, the other day I got a new mixer and MIC for my streaming setup, but when I went to put them together there was a fairly loud buzzing sound coming from my stream. By swapping cables and inputs on the mixer, I have determined that it has something to do with my gaming PC, coming from the (Green) line out port. Im wondering if this is due to the on-board sound card or something to do with voltage that I don't know about. The audio from the gaming PC still works, just with the buzzing coming over it. I have an ASUS Z170M-Plus with no sound card. Thanks in advance!

[kelvinhall05]

I'm thinking static.

[PokeyUp]

1 minute ago, kelvinhall05 said:

I'm thinking static.

Thanks for the reply! Is there anything that I could do to try and fix it without a discrete sound card?

[kelvinhall05]

Just now, PokeyUp said:

Thanks for the reply! Is there anything that I could do to try and fix it without a discrete sound card?

If it is static, then I don't think there really is a solution, but I may be wrong about both things.

[TheFlyingTraut]

Try a different cable. Sounds like a bad ground. Make sure both connections are plugged in properly. I know it is elementary, but stuff happens and things get unplugged.

[PokeyUp]

25 minutes ago, TheFlyingTraut said:

Try a different cable. Sounds like a bad ground. Make sure both connections are plugged in properly. I know it is elementary, but stuff happens and things get unplugged.

I have tried a different cable. Same setup works on another PC, but not the one I'm using. My current theory (see what I did there) is that the line out is also doing some sort of voltage to drive headphones or something, but I don't know how to turn it off. This is because it was able to drive my big headphones without and AMP, and also no buzzing sound.

[TheFlyingTraut]

Can you not do usb or optical to the mixer to rule out the line out? That sounds very funky. 

[PokeyUp]

6 minutes ago, TheFlyingTraut said:

Can you not do usb or optical to the mixer to rule out the line out? That sounds very funky. 

I don't have optical or a way of converting USB on my PC. But it may help to know that taking that cable directly out of the PC that makes the buzzing and putting it into the same green line out on another doesn't make the sound. This makes me think that it has something to do with the sound card or the port, although I was able to use the port with headphones with no problem. Thanks for the extended help!

[TheFlyingTraut]

Port could be hooped. That's just weird. Is the mixer supposed to be powered externally? Or require a certain power load?

[EsaT]

Is sound like these:

https://en.wikipedia.org/wiki/Mains_hum#Tone

That would be some kind ground loop between PC and mixer.