I didnt know if this is a receiver problem or a speaker problem, but i think its receiver, so im going to ask here ... Denon 3801 + KEF 5005 + QED Silver Anni Cable. last night i finished playing on my XBox and turned it off, as i done so for the first time my front right speaker made a loud humming noise (continually), switching the XB back on and the humming went.... I tried another input and switching hte receiver off etc, all inputs that were not active (having no device or device attached being off) result in the hum on the same speaker. turning on the subsequent device will remove the hum and the speaker sounds perfect. I thought perhaps its the speaker so i swapped the fronts over on the receiver, the speaker humming swapped - hence my thinking its a receiver problem, in specific the front left channel connectors on the denon. Anyone know what would cause this or give me some pointers, I have checked the cabling and the speakers, just dont know what to check / test on the reciever.