› Forums › The Vibe › Chat › Rant Thread! › Re: Rant Thread!
@General Lighting 454217 wrote:
I’ve just spent nearly hours sorting out a noise/grounding issue (was testing to see if I could record sound / stream from another computer). Tried every combination of sound cards, USB leads/hubs etc – and I haven’t got the kit to make up balanced cables and not all my kit is balanced anyway….turns out that the mains PSU is the source of it but the machine I was going to use for this is a old laptop with a fucked battery so it has to be plugged in.
Managed to solve it by using a even older machine to deal with the incoming audio, but it turns out that newer laptop PSU’s with a 3 pin mains connector send all manner of crap and noise down the mains earth and because of safety rules this ends up on the audio signal earth as they are normally connected together…
Yeah, switch-mode PSUs throw all kinds of crap down the earth. I was about to write a long answer, but remembered this thread on Blueroom from a while back and most of the people on there are a lot more experienced than me.
This should sort the problem and only costs £5.60. I keep meaning to get one for my toolkit for when presenters bring their own laptops and want to run video/audio off them.
Another suggestion is to take the battery out of the laptop (so the PSU isn’t working as hard trying to charge it the whole time).