Intermittent volume on Phillips W28PW6305/05?

My Phillips Widescreen has a problem with the volume, over a couple of days the volume has gone from largely being ok with the odd period of no sound to mainly no sound with the odd couple of second bursts of sound.

Any idea on what the problem is? If I need a new part then advise on how to get it and fit it would be really appreciated, it's not worth getting it done professionally and I wouldn't mind having a go at fixing it/knackering it up for good.

Also, as a side, the volume bar does not display on screen, is their an option to have it displayed?

Cheers