Toshiba 24HV10G static noise over speakers quick FIX
Good day folks. I thought you might like this one so I feel like sharing it with you, despite probably not being an issue that everybody's going to face. Someone brought me this small and "uninteresting" Toshiba 24HV10G LCD TV (by uninteresting I mean small and "boring"...I think it's a 22-24 incher) 
Anyway, the problem was that after running for a few minutes (like half an hour or so), this pretty loud and noticeable hissing sound would start coming out over the speakers. It would happen on all sources and even when the volume was all the way down to 0 (I don't know if also happened on MUTE, since the guy didn't bring me a remote for it). I took the back cover off (duuh) and my first thought was that the MAX audio amplifier IC (the small one) was heating up and coming loose, causing the noise. I blasted it with some flux and hot air, plugged the TV back in and let it run again. I was convinced that fixed it, since the noise didn't start as quickly as it did the first time, but it DID eventually come back (after half an hour or so), so the searches were still on 
I was sure it's caused by an overheating component, since that explained why it didn't happen immediately after a "cold" start, so I wanted to try the hot air method. Not knowing whether or not the hiss would still come on without the antenna cable plugged in, I wanted to test it "live" on the spot - all hooked up and everything. Trouble was, my hot air soldering station was in another room, so I went "ghetto style", borrowed my mate's windproof lighter and used that instead I swept it over the board a couple of times WHILE the hiss was happening, but didn't notice any changes. Then I put the flame closer to the main IC (the large one) and the noise got a lot worse and a lot louder. I backed up and cooled the chip by blowing on it and the noise quieted down, so that told me everything I needed to know.
Back in the shop (after also reflowing the chip for good measure) I took a heatsink which was just the right size and also got a thermal pad that I slapped over chip. That wasn't quite enough though, since the heatsink wasn't going to stay put just like that, especially since the board would stand vertically when the TV was put together, so I fashioned a bracket from a piece of metal in such way that it would go underneath the board, over the heatsink and act as a clamp to sandwich it tight over the IC. The tests went flawlessly: the TV ran for almost an entire day without hissing once
Looking back, it's surprising it didn't have a heatspreader by default, considering that even the worst, most "disgusting" Vestel boards have some sort of half-a$$ heatsink on their main ICs :|
Anyway, the problem was that after running for a few minutes (like half an hour or so), this pretty loud and noticeable hissing sound would start coming out over the speakers. It would happen on all sources and even when the volume was all the way down to 0 (I don't know if also happened on MUTE, since the guy didn't bring me a remote for it). I took the back cover off (duuh) and my first thought was that the MAX audio amplifier IC (the small one) was heating up and coming loose, causing the noise. I blasted it with some flux and hot air, plugged the TV back in and let it run again. I was convinced that fixed it, since the noise didn't start as quickly as it did the first time, but it DID eventually come back (after half an hour or so), so the searches were still on I was sure it's caused by an overheating component, since that explained why it didn't happen immediately after a "cold" start, so I wanted to try the hot air method. Not knowing whether or not the hiss would still come on without the antenna cable plugged in, I wanted to test it "live" on the spot - all hooked up and everything. Trouble was, my hot air soldering station was in another room, so I went "ghetto style", borrowed my mate's windproof lighter and used that instead
I swept it over the board a couple of times WHILE the hiss was happening, but didn't notice any changes. Then I put the flame closer to the main IC (the large one) and the noise got a lot worse and a lot louder. I backed up and cooled the chip by blowing on it and the noise quieted down, so that told me everything I needed to know.Back in the shop (after also reflowing the chip for good measure) I took a heatsink which was just the right size and also got a thermal pad that I slapped over chip. That wasn't quite enough though, since the heatsink wasn't going to stay put just like that, especially since the board would stand vertically when the TV was put together, so I fashioned a bracket from a piece of metal in such way that it would go underneath the board, over the heatsink and act as a clamp to sandwich it tight over the IC. The tests went flawlessly: the TV ran for almost an entire day without hissing once
Looking back, it's surprising it didn't have a heatspreader by default, considering that even the worst, most "disgusting" Vestel boards have some sort of half-a$$ heatsink on their main ICs :|
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