Wharfedale LCD3210HDAF crackling?

[Loz2212]

Hello, after the help I got here last time I thought I'd pick your brains with another problem.

TV frequently works fine until randomly a crackling, analogue like sound comes through the speakers and the sound than becomes intermittent. I've removed the back and when the sound begins to happen, if I wiggle the wires and tap around it makes the sound come and go with crackling, but it's impossible to pin point. Sound is off most of the time and then randomly comes back. The volume of the sound is always the same regardless of volume on the TV but if I mute the tv it stops. Headphones also don't work. Any suggestions what may cause this?

Thank you.

[ReeceyBurger123]

Re: Wharfedale LCD3210HDAF crackling?

What boards are used in this set ? Bet there is cold solder joints on the Psu.

[tom66]

Re: Wharfedale LCD3210HDAF crackling?

Worth checking this out
https://www.youtube.com/watch?v=p0PRbDme8cs

[Loz2212]

Re: Wharfedale LCD3210HDAF crackling?

Quick pic. Yeah I watched that video before. It's basically the same tv as that. I pushed that transistor and it didn't seem to make it do it or stop doing it. I've ran the iron over a few suspect joints on the PSU. It's working as we speak but it does this and then just comes back. Voltage at speakers a steady 12v where as before it was all over the place.

Thanks guys

[ReeceyBurger123]

Re: Wharfedale LCD3210HDAF crackling?

Watch this, low Pfc can cause crackling like that if not would say you the amp. Do you have an OS scope

https://m.youtube.com/watch?v=q-fEpxAlmO0

[ReeceyBurger123]

Re: Wharfedale LCD3210HDAF crackling?

Also there is a regulator in the centre of the board below the Pfc cap check that for cold solder joints.

[Loz2212]

Re: Wharfedale LCD3210HDAF crackling?

Thanks Reecey. It's behaving as we speak but I'm sure it'll play up again soon, then I'll check out those connections. No scope unfortunately. Thank you

[Loz2212]

Re: Wharfedale LCD3210HDAF crackling?

Just an update. The fault did return after I re soldered a few suspect joints on the PSU. I decided to have a look into that PFC correction fault that ReeceyBurger123 put up and remelted the solder on them surface mount resistors on the main board as well as a few cold looking joints. 2 days later and no crackling at all. Just thought I'd be constructive and let you know in case anyone else has anything similar.

Thanks for the help guys. Really appreciated.

[ReeceyBurger123]

Re: Wharfedale LCD3210HDAF crackling?

Awesome, also consider recapping the Psu. Bad caps are very common on them just so that you wont be having to open it a few weeks down the line