[jaysteels]

I was playing GTA IV on my ps3 today (Do not move this to gaming chat it's not relevant) when suddenly I began to hear a spine-tapping shreaking noise - I rushed and shutdown the ps3, but the sound kept on. I then turned off the sound system, and it stopped. However, if I removed the jack plug from the TV the shreaking would continue - So I've identified it as a problem with the tv. after shutting everything off and on again it stopped, but the noise was louder than a fire alarm and I'd really like for it to not happen again.

The TV is a Thomson 40" LCD

[finn4life]

Try muting the TV if you hear the sound again, if it continues something is broken, fixing tv's is usually a waste of time.
If not it could just be a loose antennae input.

Unless anyone else has other suggestions you're gonna need a new tv, just don't buy another thomson.

[lil weasel]

Sounds like a 'feed back'. Check the cables to your sound system. Any microphones that are connected for stuff like 'kareoke'?

[jaysteels]

No microphones, I am a trillion percent certain this ain't feedback. It's a different noise

[lil weasel]

Check for Audio cables crossed?

[Gareth Croke]

From what you've described your TV has internal speakers as when you removed the jack it still continued. If that is the case the your TV is, to put it technically, broken. It could be a software issue with the sound chip causing a digital feedback within the TV (no mic required in Digital Feedback).

You would need to check if your TV is within warranty and if so claim on it and if not then you might need to get it repaired if possible (cost prohibiting)

[MIKON8ERISBACK]

Does your home's electrical system include a ground wire at the wall sockets? And does the power cord that the sound system uses test positive for proper ground continuity? If a lack of ground continuity isn't the problem my best guess is a defective IC (integrated circuit) chip in the amp (extremely common nowadays). In that case, your amp is rendered a complete piece of sh*t until the defective IC is replaced.

[Spider-Vice]

You said you disconnected your sound system and it stopped. Yet when you removed the jack from the TV it didn't stop, it could be the sound system instead of the TV, feedbacking.

[MIKON8ERISBACK]

The next possibility is a ground loop. Is another sound system on the same circuit that shares the same ground? If so, than a battle between the two sound systems over which one gets the ground connection is the next thing that rings a bell. In that case, get an ground loop isolator.