fender jazz bass knobs

Bass amp and a buzz if I'm not touching something metal?
I have a Fender Squire Jazz Bass, with a Fender Rumble 15 bass amp. In the area of the under three commanders – two large, one small. The small (I have no idea what is officially called) has been giving me a little headache. When you turn knob to the fullest, my amp starts making a loud buzzing noise. As soon as I touch anything metal on the guitar (strings, reels, etc.), the buzzing stops until I let go. The higher the knob is turned, the higher the noise. If I turn the knob down to minimum, the noise stops. I am sure that is still there and I can not hear me. Of course, the higher the control is set, the sound is richer. I like the richness of sound, but hatred. Do you have ringing Anyone know what specifically is causing this noise, or why only occurs when the knob is turned. And of course, how I can fix it?
The noise is a problem of soil. The noise goes away when you touch something, because the system is partially grounded through you. This can be a very dangerous if there is something wrong with the wiring inside the amplifier. Its likely that the problem of land is in the guitar or guitar cable. Make sure the power cord its NOT amplifier has a pin cut. If it was designed to have a 3-pin plug and one was cut, you are in danger.
Fender Vintage Modified Fretless Jazz Bass