Frustrating Grounding Problem (HISS/BUZZ/NOISE)

Something very strange happened...

I went back to the original configuration - the one that caused the grounding issues with the accompanying noise, etc. (i.e. I removed the back-up power supply from the chain because I needed it for something else) and poof...the problem is magically and curiously gone!! No buzzing, no hiss, no apparent ground loop problem whatsoever!

Yet, everything is (almost) exactly as it was before. The laptop and monitors are plugged into the same power-bar, just like before, but, I'm not experiencing a grounding problem. Why? How did it go away, seemingly, on it's own?! This is baffling.

The only thing I can think of is that it has something to do with the new external sound card. I had mentioned in a previous post that I thought that an external sound card, with it's own power supply, might solve the grounding issue. I tried it, and at first it didn't make a difference. I think that the introduction of this sound card COMBINED with a new plugging arrangement, which I arrived at accidentally, may have eliminated the ground loop issues. 

I just hope it doesn't magically reappear. 

I just hope it doesn't magically reappear. 

Well, if it magically went away, the chances of it magically coming back are quite good, and since you don't know what the magic is, this might be a bit of a problem...

But it's almost certainly loop-related.

I'm not trying to scare you, but it would be remiss of me not to mention one other possibility, and that is that you've blown out a ground safety resistor somehow. This would have the effect of raising one of the looped items in your signal chain high from ground, which might be enough to stop the problem, but could also leave you with an item, which if disconnected could end up with a dangerously high chassis potential - simply by capacitive coupling again. I managed to do this to my Proton preamp at one stage - and it was the laptop power supply that was directly the cause of this. I've altered the entire arrangement since then  to prevent it happening again, but this took quite a rewire.

Well, if it magically went away, the chances of it magically coming back are quite good, and since you don't know what the magic is, this might be a bit of a problem...

Yes, I feared as much. However, it will be ok if it buys me enough time while I save up for a computer.

But it's almost certainly loop-related.

I'm not trying to scare you, but it would be remiss of me not to mention one other possibility, and that is that you've blown out a ground safety resistor somehow. This would have the effect of raising one of the looped items in your signal chain high from ground, which might be enough to stop the problem, but could also leave you with an item, which if disconnected could end up with a dangerously high chassis potential - simply by capacitive coupling again. I managed to do this to my Proton preamp at one stage - and it was the laptop power supply that was directly the cause of this. I've altered the entire arrangement since then  to prevent it happening again, but this took quite a rewire.

Haha, I didn't considered this possibility at all. So I can potentially shock myself?! It's amusing in an ironic kind of way. I had never suspected that purchasing new monitors could lead to this.

I'll wait a bit to see whether it returns, before I start doing any "rewiring", give the fact that I'm completely unqualified to do anything of the sort.

[I FIGURED IT OUT!!!!!!!!!!!!!!!!]

I FIGURED IT OUT!!!!!!!!!!!!!!!!

I had to move my laptop today. When I brought it back to the studio the noise and hiss and mess came right back!! Just as "magically" as it disappeared. No surprise there! Ohh the pain....the horror....it almost brought tears to my eyes! So I decided to move stuff around again in the hopes of finding an arrangement or placement that would bring back the peace and quite that I had enjoyed over the past week or so (a tease). 

I finally figured out the problem...so simple...it was the laptop adapter!  It had been sitting on the table next to the speakers the whole time.  I moved it AWAY from the speakers and THAT eliminated the problem entirely. I almost can't believe this. 

So the lesson learned is that if you experience grounding related problems involving a laptop, try to put some distance between your laptop's adapter and your speakers.* I'm not saying this will work in every, or even most, situations. It likely won't. All I'm saying is that this worked for me and that it's a quick and simple way to rule out a factor. Let it be one of your first steps.

*Edit, June 6, 2007: For any of you out there who run into the same problem, note that it's not just about putting distance between the adapter and the monitors. I tried that before and it didn't work. It's about placement, in a manner quite akin to positioning a TV antenna.  You have to play around with the placement quite a bit (centimeters seem to make a difference) to find the noise-free sweet spot. I sometimes knock against the adapter with my foot and the noise returns. I then have to move it around again to find the sweet spot.  It sounds like more of a pain than it really is.

Given the basic limitation of the card, it has to be said the KX drivers are a real mess.  I've never made them work properly, they're confusing and they are as ugly as sin.

Much to my dismay, when I tried the drivers, I got even more lost. I reverted back to the original. Thank you "Echo"

BTW, Sssshh!!!  Must_know, that's basic. A baby could've worked that one out.   My problem is with a fridge even SteveG doesn't want to talk about but at least I know the problem

Only kidding, glad you got it sorted.

My problem is with a fridge even SteveG doesn't want to talk about but at least I know the problem

Your fridge only hums because you haven't taught it the words yet...   

Given the basic limitation of the card, it has to be said the KX drivers are a real mess.  I've never made them work properly, they're confusing and they are as ugly as sin.

Much to my dismay, when I tried the drivers, I got even more lost. I reverted back to the original. Thank you "Echo"

BTW, Sssshh!!!  Must_know, that's basic. A baby could've worked that one out.   My problem is with a fridge even SteveG doesn't want to talk about but at least I know the problem

Only kidding, glad you got it sorted.

I agree, it's as basic as it gets, yet I completely missed it, which i'm a bit embarrassed about, I must admit.

Your fridge problem slays me.