TV mains hum

[EDDIE51]

Our TV an LV plasma screen has started making a mains hum when it is turned on. The hum gets louder as you turn up the volume, there is also some pixalating of the picture. Anything that can be done ?

[bazwillrun]

i take it there are no problems with any other household equipment plugged into the mains supply.

try it in another socket

apart from checking all the cables (dish, ariel, speakers etc etc) are all properly and firmly connected not much, sounds like a job for a repair person.

unless you try the old school method from the days of CRT and tubes..give it a wallop and see if that cures the problem !

[EDDIE51]

We have 2 TVs the same in the house but only the upstairs one has the problem. does this make a difference ?

[Zacs-Master]

Is it near any other electrical equipment?

[EDDIE51]

No not near anything else apart from a table lamp.

[EDDIE51]

It works from a Virgin media box as does the other one.

[Zacs-Master]

Try swapping the TVs round. If the other one hums then its interference from something.

[Hymie]

You say that the mains hum gets louder as you turn up the volume; do you mean that the hum becomes louder in terms of the ratio of hum versus wanted sound – or that it increases in proportion with the wanted sound?

Is the hum present regardless of audio input source (set top box signal, aux/phono input etc)?

First, determine whether the mains hum is present within the audio signal supplied to the TV or that it is being generated within the set.

[EDDIE51]

The Hum is in the set changing the digital box makes no difference.

[Hymie]

It could be number of things causing mains hum to be generated within the set (from the loss of an audio signal screen earth connection, to component failure etc).
Other than having the set repaired, you could consider muting the TV and feed the audio signal through your hi-fi (or other audio) system if the sound as is, is unacceptable.