[trailofdead]

I'm having an issue when I use a headphone extension interconnect where I get static/humming or squealing type of sound, even when nothing is playing. It only happens when I plug the interconnect (15 ft Canare Star Quad L-4E6S with neutriks 1/4 plugs) into my MM stack. I've tried different headphones and still get the same sounds. I can move the cable around and the sound will change or go away. I've tried plugging the cable into the headphone out on my receiver and dont hear anything and I've tried on different headphones. If I plug my headphones directly into the MM stack, I dont hear the noise.

I should add, MM is next to a speaker and under two monitors. Also, when it was plugged into my receiver, I tried moving the cable around to the same area that it would have been in if it were plugged into the MM and didnt hear any noise.

What is the cause of this noise and how do I stop it?

Thanks

 

[NA Blur]

It sounds like a poorly shielded cable or lack bad ground in the questionable cable may be the culprit.
 
Can you post a picture of the cable ends for the various cables you are testing making sure to reference the one that gives the noise?

 

[trailofdead]

I'm not at home right now, so I cant post pictures.  The ends are three pole stereo jack with solder connections plug and three pole stereo plug.
 
Just tried unplugging the usb DAC and the noise mostly went away.  Tried two other usb cables, the shortest being 3 ft and there was still noise.  Tried it in the other room using my laptop, away from my router, desktop computer, and cellphone and it the noise seemed greatly reduced.  

 

[dvw]

It sound like a bad solder joint. Use a multimeter to check out the integrity of the cable. Also check if the jack is bent. It can be the male or female. Often time during disconnecting, the pull might break the cable and cause a bad connection but not a broken connection. That's why when you move the cable the noise sometimes disappear. If you're handy with soldering, you can try and fix it. Extension cable aren't expensive. It's easier just to replace it.

 

[icebear]

Have you found a fix yet ?
It could also be a so called ground loop. I.e. you have a different ground potential at the various equipment housings. Do you use different wall outlets for all that stuff that is plugged to the AC? Try using one wall outlet for all you hifi/audio related stuff and use a different one for the PC and monitors.

 

[trailofdead]

I have not found a fix yet.  I've been sitting in a chair closer to the amp instead of on the couch.  
 
I'll look into reading up on the ground loop.  I'm not using a different outlet for audio and PC stuff, but I guess that would explain why it was better when I went to the other room and when I used a different amp.  It seems like when I have my hand near the female plug, the noise goes away.  Not sure what that means.

 

[dvw]

Ground loop are caused by a difference in the ground potential between two pieces of equipment. It will be a constant hum and will not go away when you move the cable. If it's better (the noise did not go away) when it's with a different amp or in a different room, this could mean the problem is in the plug. Particularly if moving your hand close to the female plug reduces the noise. This indicate you definitely has a grounding problem. It is very likely you have a bad connection at the ground pin of the plug. It also seems like the connection is on and off depends on the stress of the cable. Try rotate the plug (without moving the cable) and see if you can find a sweet spot. If so you'll need to replace the plug. Good luck.

 

[trailofdead]

 
Just tested the cable with my HE-400s and I cant hear anything.