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LOAJ3256, Technician
Category: Home Cinema System
Satisfied Customers: 307
Experience:  35 years in Home Theater and Systems Integrator, Senior
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Why is my Hi tech hifi speakers humming/buzzing when I switch

Customer Question

Why is my Hi tech hifi speakers humming/buzzing when I switch it to on position?

Please assist I need help.
Submitted: 4 years ago.
Category: Home Cinema System
Expert:  Steve G. replied 4 years ago.
Hello there and welcome to Just Answer. My name is XXXXX XXXXX I will be assisting you today. I am an engineer with over 30 years of electrical and electronic training, repair and installation experience. I will try and answer your question accurately and precisely so that we can get you on your way.

Now..this sounds like a powered speaker of some kind. Can you give me an actual part or model number please?
Customer: replied 4 years ago.

thanks Steve, the model - 618.


mobile multi media amplifier - built in mp3 player.


power - 30 w - 150 w


F/R - 38 hz - 20 KHz


impedance 4 ohms


Sensivity - 88 dB


A/C 220/240 V - 50/60 Hz


As soon as I switch the power switch on position the speakers starts humming/buzzing and you can not control it with the volume its a straight humming sound from the speakers.

The second thing I did myself was disconnect the speakers and powered the unit and there was no sound but as soon as I hooked the speakers it started again.

Expert:  Steve G. replied 4 years ago.
What else is plugged into the system? An iPod for example?
Customer: replied 4 years ago.

The system has one USB port and a SD/MMC card slot for playing music.


Also it has a mic 1 input port/mic 2 input port and a guitar input port.

Expert:  Steve G. replied 4 years ago.
Ok, but nothing is plugged in to any of those?
Customer: replied 4 years ago.

Yes, thats correct I do not plug anything into this ports but I use the USB port & SD card port for playing music.

One more thing I forgot is the toroid transformer gets very hot when switched on.


Toroid transformer - input 220V/50Hz

output 24V- ov 24 V


Expert:  Steve G. replied 4 years ago.
I just don't have schematics for that thing. I am going to opt out of this question which will allow other electronic experts to chime in. I'm sorry.

Hold on.
Customer: replied 4 years ago.

Hi steve,

Thanks alot.


Who is assisting me right now?

Expert:  Rusty replied 4 years ago.

Hello, my name isXXXXX it make any difference when you plug it into a different power source? Are there any dimmers, or flourescent lights in the area? High transmission power lines?