guitar humming

[moody]

guitar hum even at 9oclock knob Overdrive amp settings

i've got a humming problem on my epiphone les paul when my Overdrive amp gain knob is at 9 o clock. I dunno whether is the pick up problem or not but i sent my guitar at a shop and then i tried on that shop's amp and my les paul did'nt even give a hum. it was perfectly normal. The shop rewired my guitar because it was wrongly wired and when i came back home, it still gives that hum sound at the same overdrive amp gain settings. my friend use his Own guitar and tried it on my amp and it does'nt give that hum sound. can anyone help? =\

 

[Jumpin'Jellybean]

Is your amp grounded? What guitar does your friend use? Humbuckers generally don't give a hum. Or give much less than regular single coils. What shop is this? Did you verify the problem with another shop?