Why does my guitar make noise when its not being played??

Question:

Why does my guitar make noise when its not being played??

When i turn my amp on, and i first pick up my guitar and silence the strings, as soon as i let my fingers off the strings, they all start vibrating and making noise. Especially the low E thru G strings. Why??? They aren't being plucked or picked, im just sitting there. They start off dead quiet, then suddenlt get louder and louder and louder and i cant figure out why! If i turn my volume down on the guitar, then it's not as noticeable (obviously?) but its still there. What gives?

Best Answer - Chosen by Asker: Don't face the guitar toward the amp at a close distance. Also, check the back of the amp for a polarity switch. If it has one, flip it.

Also, check your Volume and Line settings. And make sure you have a 3-prong plug put into a wall outlet, and not an extension cord.

I hope this helps.