Speaker Hum :(

[#1]

when i have my speakers on standby 5.1 microlab FC730 , i get a constant HUMMM 
had the same with the old Logitech set , so all i presume is it some interference from my mains  .
is there some way of removing this as the hum is annoying 

[#2]

I have a Logitech 5.1 speaker set that has developed a mains hum and I'm assuming a component has failed in its power supply.
It's therefore consigned to the skip.
Does it hum when nothing is plugged into its input socket?

[#3]

Move the speakers to another room and plug in away from any other electrical stuff.
If the noise stops then you might just need to relocate the speakers.
If the hum continues, plug them into a personal stereo player etc without the unit playing - if it still hums then there is possibly a faulty smoothing capacitor in the power supply stages of the speakers. If the hum stops then you might find a 10k resistor from each input to ground will cure the problem.

[#4]

I have a 5.1 surround sound that someone gave me on freecycle. It was advertised as having a bad humming sound.
Having had tons of dodgy electricals over the years and 'making do' I applied and luckily got it. I got it home and plugged it in and yeah.. it was humming alright... pretty badly so actually. There was no way you could put up with it.
Not being afraid to use a screwdriver I took the thing apart. The cause was immediately obvious - an electrolytic capacitor had gone bad. We don't have a Maplin nearby so I went to the local TV repair shop and gave him a couple of quid for a replacement. Soldered it in and years later it's still working well.
People always used to say things like its a 'bad earth' and stuff like that (what that really meant was a duff connection) but electrical equipment thats working properly shouldn't do that. Solder doesn't just become intermittent unless it's a dry joint and thats rare for manufactured stuff. The chinese are known for manufacturing duff capacitors as they stole an incomplete formula many years ago. So bad is the problem that there is even a website for it - badcaps.net

[#5]

Perhaps they hum, because they don`t know the words 
/:coat 

[#6]

LOL shutter 
they do hum when they are plugged in alone every  thing else off , and when plugged in to another socket .
they are only 2 months old , they have a separate AMP , am sure that its due to the house main circuit  , there must be some way to isolate the socket ?

[#7]

More likely that they have some duff chinese capactors in them.
On a similar note I use one of these as my sound for the PC:

Despite being great with MP3 players etc, it picks up the graphics chip in my PC operating and outputs a buzzing/ crackling sound at the slightest change on the screen - everything from a mouse moving to scrolling a page.

[#8]

Old fashioned valve amplifiers, and valve amplifying circuits in radios, used to suffer from "mains hum", which was due to using incorrect values of "de-coupling" capacitors... or the breakdown of de-coupling capacitors... on the power supply rail, and the valve heater rail....
I don`t know how modern "chip" circuitry deals with that problem...
I doubt that Isolating the mains lead/plug will do the trick. 

[#9]

You might have an earth loop.
https://en.wikipedia.org/wiki/Ground_loop_%28electricity%29

[#10]

vilefox   that sounds like the problem ,
so what is the answer to stop it ?
maybe one of these may help , with the help of a bit of google 
http://www.maplin.co.uk/tacima-2m-six-socket-mains-conditioner-plus-rfi-filter-for-home-cinema-and-h...

[#11]

Or you could try what I suggested above, relocate it, plug it into a *portable* personal stereo type device and see if the hum stops.
If it doesn't then it is unlikely to be an earth loop.

[#12]

Most speaker systems use external wall-plug or power 'brick' type power supplies.
Could you find (borrow) another power supply with similar voltage and connector size, and temporarily see whether the hum disappears
A few months ago, my 'Creative' speakers started humming, I borrowed the PSU from one of my wireless access points to prove that it was indeed the original power supply that needed replacing.  Having identified the problem the replacement PSU only cost about £4 on eBay.

[#13]

With the above in mind.... I am minded to refer you to my previous statement in the house !...

Quote from: shutter

I doubt that Isolating the mains lead/plug will do the trick.

So save your money, don`t get a Maplin extension lead ...... yet !

[#14]

i have tried connecting to a different source , its still there 
the Power supply is direct into the amplifier not via a transformer sorry purleigh
my system http://www.microlab.cn/product_detail.asp?id=223&bigclassid=15&smallclassid=63

[#15]

Earth loops:-

(from http://www.soundonsound.com/sos/aug06/articles/qa0806_4.htm ).