Buzzing sound from my Subwoofer

[joremi2]

Hello,
I recently bought a Logitech 2.1 Z313. After using them for 3 months i realised something:
1.when I touch the plug-in jack with my fingers or put it in the PC, a very loud buzzing sound comes from my speakers and subwoofer.

2.It occurs on any device. And If i touch it in the end an electricity hits me

3. the microphone get's this humming sound when i use the speakers so i can't really talk through any microphone without Buzzzzzz.
Please, help.

 

[Bruce Hugo]

Greetings,

Title/Intro:
There is some conflicting info between the title and body of text, is the sub buzzing, or all three speakers?
While the sub appears to be active (having ac power input), the others appear passive.
If you touch the end of 3.5mm trs connected to the 2 main speakers, it shouldn't make noise, and definitely not a very loud one.

1:
In this first point, what is described is live insertion, though if I give the benefit of doubt, I imagine it's intended to mean that it buzzes continuously while plugged in. If not, just leave the speakers plugged in, or power down the amplification before switching connection.

2.1:
Good information if accurate.

2.2:
I have to assume this still references the jack. I don't know what that indicates.

3:
I didn't see a microphone in the amazon listing, so, I assume this is just why you want it fixed, and not diagnostically relevant information.

Okay, 3 months is a long time to not notice "very loud buzzing", so I assume it's more subtle.
Point 2 eliminates the source being the cause.
Point 1 indicates that the problem occurs only when you complete the circuit.

I imagine your problem is 50/60Hz (mains) hum, or a ground loop

Consider adding a ground loop isolator, might work.

Best of luck.