Problem -- Samsung monitor speaker hiss

Hello everyone,

Over the last three weeks or so my Samsung SM171P LCD monitor has started to emit a loud hiss and crackle from the built-in speakers when powered up. After a few minutes it slowly dies down to silence but it's getting louder and lasting longer every day.

It happens comes out of a period of standby more than half an hour as well If you turn it off then back on once it's warmed up it doesn't do it.

I have unplugged everything, taken it to another room and powered it up with nothing but the power connected and it still does it so I know it's not interference or a loose cable.

So it has to be an internal but I'm not the best with a soldering iron!

I'd appreciate it if anyone could give me any hints as to what might be causing this and sort of fault to look for if I decide to get inside it?

Thanks in advance, Chris
PS I know this isn't strictly graphics cards but it wouldn't allow me to submit without a sub-category so I had to pick one!