Humming noise in Harmon Kardon AVR 110

Does the hum go away when you change inputs?

Ensure that your speakers are connected to the terminals that you have your speaker selector switch turned to.
Then check that you have your device, whether it be a CD or DVD player, or turntable, plugged into the correct input and that you also have the correct input selected on the receiver.

yea try use in a monster power strip it clears al of that up it is picking up noise from all the wires

mute the inbuilt speakers you can hear the sound from the external speaker

I think I had the same problem. This is how I fixed it.

I have my vizio 42 hooked up to a Harmon Kardon surround sound, and the digital cable box. Essentially, I can adjust the volume 3 ways - through the tv, cable box or av receiver. The humming sound happens when you have the volume maxed out on the av receiver and not the cable box.

For example, the sound level on my Harmon Kardon goes from -10 (lowest) to 10 (loudest), with 0 being the middle ground. The buzzing was happening when the Harmon Kardon was set to 10, and I was using the cable box volume to adjust the sound. To fix it, I turned down the volume on my receiver to 0, which may be about 50% max volume of the receiver. Then, I switched devices and used the volume on my cable box. This got rid of the static I was getting. Hope that helps.

Usually Humming noises come from frequency interferance.  In this case it is being caused by your input sources.  A smiply solution is to replace the cables and or seperate the source cables away from any electircal cords or sources.

My receiver started having same problem after about 2 years from install. Any ideas?

plug eash units sound in red whites from dvd tv main out the set speaker wires in place front ch a ok turn it on make sure ch a speakers on only select corect video input dvd ect turn it up

Check capacitors in power supply......also check for over-heated
resistors..all 1 ohm.....replace if cooked...................T.

Looking in the manual (link below) I see that this receiver uses 8ohm speakers, check that your speakers are 8 ohms or more. I think that connecting 2 sets of speakers to the same output is the problem as when you connect speakers in parallel (i.e. just twisting both pairs of wires together) you effectively half the impedance. So if 2 sets of speakers of 8ohms are connected this way the result will be 4ohms which is too low and will cause the unit to go into standby. Try removing the additional front speakers & see if the fault persists. If it does then it is likely a fault in the wiring. http://www.harmankardon.com/product_support/support_detail.aspx?Region=USA&Country=US&Language=ENG&cat=&prod=AVR%20110&sjump=om&#active