question? when reading the owners manual for ground balancing the mxt it talks about the threshold and how you should hear a soft hum. I've never heard a soft hum on my mxt. it is a broken signal of various levels. so i just turn it down an don't deal with it. if i do not get this soft hum the manual refers to does that mean my mxt is not working correctly? or, am i just doing something wrong. plus when i pump the coil up and down like the manual says to do i hardly get any noise at all unless I'm over a target. so i move to another spot and try again. no noise to speak of comes from the machine to so it's like am i doing this with the detector off. i had a qxt prior and when i balanced it i could tell the machine was doing it balancing thing. I'm not confident I'm balancing this mxt correctly. any suggestions would be greatly appreciated. i ordered a 4.5x7 excel coil and want to get the max out of my machine/coil. thanks and hh to all.