[TheGiantHogweed]

I have just got an LED Dimmer switch. This is now on the wall and controls my ceiling light. This may sound like it has nothing to do with audio but my amplifier seems to buzz quite a lot though my speakers weather direct is on or not! They must just link up somewhere. Even through my headphone amplifier (the FiiO E10) through my PC, I can hear the buzzing when the wall light switch is on. To me, I really struggle to understand why this is happening. The noise must be traveling from the switch to my wall outlets to my PC and then through the USB to by E10 DAC. This DAC feeds my Pioneer amplifier through the line out and my headphones through the headphone out. The sound is noticeable through both.
 
However, very strangely, unplugging the COAXIAL cable from my LG Blu-ray seems to have totally stopped that sound. The player was switched off at the wall in the first place though making it even more strange. Even just unplugging that HDMI cable form the Blu-ray player also stops it.
 
Just to make things clear, both my PC and my Blu-ray player link up to my Pioneer amplifier through 2 separate audio inputs. The solution for now as I said can be just disconnecting the HDMI cable of the Blu-ray player when it isn't in use. When I do use it and put the amplifier onto the correct input for it, the buzzing sound through the speakers isn't really there. It is more when I have the input for my PC selected on the amplifier.
 
 
Hope this makes some sense. I would much appreciate to know the possible reasons behind this. That is if I have described clearly enough.
 
 
Thanks.

 

[MindsMirror]

The LED dimmer probably uses a PWM signal to control the intensity of the lights. It turns the lights on and off very quickly, too fast for you to see, but not too fast for you to hear. I don't know a lot about these type of problems, but it might be EMI, power supply noise, or a ground loop issue caused by the pulsing of the LEDs that is reaching your audio equipment somehow.
 
Can you describe how your devices are connected to the power outlets? Perhaps rearranging that somehow could fix it.

 

[TheGiantHogweed]

  The LED dimmer probably uses a PWM signal to control the intensity of the lights. It turns the lights on and off very quickly, too fast for you to see, but not too fast for you to hear. I don't know a lot about these type of problems, but it might be EMI, power supply noise, or a ground loop issue caused by the pulsing of the LEDs that is reaching your audio equipment somehow.
 
Can you describe how your devices are connected to the power outlets? Perhaps rearranging that somehow could fix it.

Well, I have 2 double UK socket outlets in my room. I have an extension plugged into 3 of them. Even when I plugged my amplifier into a socket directly, the noise is still there. I have a very similar problem with an LED strip with a dimmer too. Only with this, putting the amplifier on direct prevents any of this noise being noticeable.
 
I do have a huge amount of devices but I feel that is is something related to my blu-ray player or my PC. They are both plugged into the same 6 gang extension. However, my amplifier is on the other side of my room in another extension from the other double wall socket. I find it very puzzling but I suppose it does all link together somewhere.
 
I just find it so strange that unplugging the HDMI cable form my blu-ray player stops the buzzing through my speakers when it is related to a dimmer switch on the wall!
 
Even when I try to listen to the bulb or switch, there is no noise (that I can hear) at all. The amplifier just seems to pick it up and play it through the speakers which is mainly irritating when nothing is playing or during quiet music. Most annoying is through my headphones where I can hear every little detail.
 
As I said though, there is a solution but it seems a bit strange that that was the only thing I found so far that solved it.
 
Thanks for your help anyway.

 

[MindsMirror]

The LED dimmer is not creating sound noise, it is electrical noise. The LEDs and the Blu-ray player might be wired to the same mains power circuit, while your amp which is connected to a different socket is on a different mains circuit. The connection of the HDMI or coax cable creates an electrical connection between the two, so the noise might be able to get through somehow and upset the amp. Can you try connecting the amp to the same extension as the other components?

 

[TheGiantHogweed]

This will be a bit hard to do as the amplifier is on the other side of my room. I may be able to find a long enough cable but it won't be able to stay like that. It will be worth testing though. The switch on the wall is part of the lighting circuit and doesn't have a plug and this is why I find it strange that the noise I hear gets to my amplifier.
 
It is more understandable with my LED strip that just has a 12v power supply plugged into the same extension as my amplifier.

 

[MindsMirror]

The lights are not plugged in to a wall socket, but they may still be electrically wired to the same circuit that feeds one of the sockets.

 

[TheGiantHogweed]

I have my Freeview box plugged into the same 6 gang extension as my PC and blu ray and that doesn't seem to improve anything if I unplug the HDMI from that. This also does go to my amplifier. Unplugging the USB cable for my E10 also solves it but then I get no sound from my PC to my speakers or headphones. I use that much more often so just unplugging the HDMI from my blu-ray player is enough for now.