current in monitor's signal cables

[crepuscular]

By chance I detected that the signal cables of my monitors have an electrical charge, I do not know what voltage but using a meter indicates activity. The strange thing is that this still happens with the monitors turned off , connected to the electrical grid but without being connected to the sound card . So this current doesnt comes from computer.
I'm going to ask in support of the manufacturer, but I wanted to ask here too. btw, they are Presonus Eris E5.

[windspace]

Q. What meter are you using?
Q. Assuming the the monitors are self-powerered?
Q. What happens if you completely unplug the power supply to the monitors? It sounds like the meter is indicating voltage, not current. It should go away when to power cord is completely disconnected from wall outlet.
Q. Have you noticed any audio artifacts that led you to measure voltage?

[Radio Fornax A]

As windspace said what kind of meter are you using? Could you actually be just measuring resistance in the cable if it is set to resistance/ohms?

[crepuscular]

Thanks for asking, i dont known whats going on here but my place isnt grounded , so I will ask to an electrician, I dont have proper tools, just a standard current detector; im using this:

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