Hey guys, I was wondering can Electric Guitar Amp Buzz (not caused by the amp) be harmful to the guitar or the amp itself? The reason I say its not caused by the amp is because when i unplug the guitar cable from the input jack the buzz goes away. My guitar is a open coil humbucker. So again, I was wondering if the Electric Guitar Amp Buzz do any damage to the guitar or the amp itself?
No, it won't hurt your guitar. It is no good for you amplifier's speaker, but your guitar will be just fine.
"Maybe this world is another planet's hell?" - Aldous Huxley
As FatalGear said, nope, it wont hurt your guitar at all! If you use a distortion pedal (like I do!), then that is what is causing the buzz! I own an Epiphone Les Paul Jr (which has an open coil humbucker!), and there is no buzz whatsoever without my rig...
Epiphone Les Paul Jr

Marshall VT-1 Vibratrem
DigiTech Hot Head Distortion
DigiTech Digital Delay

Kustom Dart 10
check the ground (round prong on your amp cord) and also the electrical outlet. could be a bad ground. also the wiring in your guitar could cause the buzz