eliminating speaker feedback/interference

[nwrigley]

I had my computer audio outs and my TV audio outs plugged into my stereo at my old apartment. The stereo has 3 set of audio inputs and I never had a problem with it before.

I recently moved and now when I try to set it back up the same way I get buzzing/interference when both sets of cables are plugged in at the same time. It doesn?t seem to matter what they are plugged into and they both work without issue when plugged in separately, but as soon as the plug hits the metal of the input I get feedback if the other input already has plugs in it.

So, everything worked without a hitch when I had it setup this way before and each input or set of cables works fine on their own but now when both are plugged in at the same time. Anyone know what might be causing this?

 

[nwrigley]

I've messed around with it more and have new info. It works fine when I replace the pc connection with a portable cd player (no feedback). So the feedback seems to be coming from the pc, but again, it works fine unless that tv is also plugged in. I have no idea why this would be the case. I also tried different cables without any luck.

Does anyone have any ideas?

 

[tk11]

Connecting components that use different power outlets can cause ground loop noise.

 

[nwrigley]

Originally posted by: tk11
Connecting components that use different power outlets can cause ground loop noise.

I had never heard that before. They are definitely plugged into different outlets at the moment. I'll try using the same ones when I get home, thanks.

 

[Silx]

Not all of your outlets may be grounded. I've lived in an apartment before where not one outlet was grounded. I had the same buzzing problems, and in order to fix it, I took some high gauge wire, screwed it to my PC case, and then wrapped it around one of the heat water pipes that went through the radiators along the walls. It fixed the buzzing! I had to sand down the paint though, because the wire has to touch metal.

This is probably the cheap-man's solution but hey, buzzing noises are annoying, right?

 

[nwrigley]

Originally posted by: Silx
Not all of your outlets may be grounded. I've lived in an apartment before where not one outlet was grounded. I had the same buzzing problems, and in order to fix it, I took some high gauge wire, screwed it to my PC case, and then wrapped it around one of the heat water pipes that went through the radiators along the walls. It fixed the buzzing! I had to sand down the paint though, because the wire has to touch metal.

This is probably the cheap-man's solution but hey, buzzing noises are annoying, right?

It's funny that you should mention that. I actually had to have an electrician come and fix one of the outlets that my surge protector detected as not being grounded. They should all be good to go now.

I'm in the process of moving and had to unplug the stereo, so I haven't had a chance to test it out any more.