Jump to content
House Price Crash Forum

Archived

This topic is now archived and is closed to further replies.

inflating

New Led Tv Loses Picture But Audio Continues

Recommended Posts

Any ideas what the problem might be?

It's a

http://www.youtube.com/watch?v=U13tLdKUVac

and problem just started, as the set is only a few weeks old. Suddenly the screen goes blank (black) and there's no video, although audio continues as before. For the first minute or two the picture comes back for a moment or there are flashes of bits of the video picture signal on the screen for milliseconds and then back to the blank screen again and that's how it stays until the TV is unplugged for 3 to 5 mins and then plugged back in.

The set connects online as it's a Smart model, and the firmware auto-upgraded a week or so ago, while this problem only started yesterday. When the screen is blank, I can see a white (backlight?) at the back of the set, but the screen remains dark

Is this an overheating component, software problem or.....?? Anyone know? I have to repack and send the set by courier for a repair otherwise and it's a right drag doing that.

"They ain't 'arf built well" - er...jury's out on that one.

Share this post


Link to post
Share on other sites

Does the problem happen with multiple sources (i.e. watching broadcast TV and a DVD), or only one?

If it happens regardless of the input source, the problem sounds to me like a faulty capacitor somewhere, and if the thing is still under warranty I'd take it back.

If it only happens with broadcast TV, this says to me a reception problem that degrades the picture data but not the sound data (much lower bandwidth). Try a signal booster on the aerial?

If it only happens with an external input source, try a new video connection lead. In particular, cheap HDMI leads are notorious for failing.

Share this post


Link to post
Share on other sites

Send it straight back.

Problem is they haven't got any more at the price. They were new but end of line.

Does the problem happen with multiple sources (i.e. watching broadcast TV and a DVD), or only one?

If it happens regardless of the input source, the problem sounds to me like a faulty capacitor somewhere, and if the thing is still under warranty I'd take it back.

If it only happens with broadcast TV, this says to me a reception problem that degrades the picture data but not the sound data (much lower bandwidth). Try a signal booster on the aerial?

If it only happens with an external input source, try a new video connection lead. In particular, cheap HDMI leads are notorious for failing.

Thanks TAB

So far it's only happened when receiving satellite TV.

Of course, once the screen goes blank, you can't see anything. You can press the TV set remote for Menu or anything you like and nothing's visible on the screen. If I switch the set to standby and back on, no joy. But if I unplug it for 3 to 5 mins, the pic comes back.

As I type, I've reset the TV, just in case the firmware upgrade did this (although that was at least a week ago).

Share this post


Link to post
Share on other sites

Push the Scart or HDMI lead in firmly.

Thanks D

Yes, there is a good quality HDMI v1.4 in use and I did so already. It seems fine :unsure: SCARTs (unless top quality) I've given up on as the pins cause a lot of grief in my experience.

Share this post


Link to post
Share on other sites

I bought a 42" LCD for £25 recently, the volume is stuck on max

For that price, I couldn't turn it down

Share this post


Link to post
Share on other sites

I bought a 42" LCD for £25 recently, the volume is stuck on max

For that price, I couldn't turn it down

Can't you get a techie to check it over and fix the sound? Maybe you can mute the main output and get audio out through the phonos/rca at normal levels to a home theatre system?

Oh I geddit, couldn't turn it down, ohhh groan :P

Share this post


Link to post
Share on other sites

Check their website to see if there is a firmware upgrade, it is easy to do, USB memory stick with my Samsung.

Also, sometimes the auto tune picks the wrong transmitter and you have to manually tell it what channels to search. The freeview website will tell you.

Does it blank on DVDs too?

Share this post


Link to post
Share on other sites

Check their website to see if there is a firmware upgrade, it is easy to do, USB memory stick with my Samsung.

Also, sometimes the auto tune picks the wrong transmitter and you have to manually tell it what channels to search. The freeview website will tell you.

Does it blank on DVDs too?

Thanks.

The blanking is the TV, not the source. It's just a question of whether the source triggers it somehow.

It's only done it while tuned on sat so far, not DVDs or the normal TV signal.

It's connected to the net so it firmware upgrades on its own, and did one a week ago, but the problem only started yesterday.

Gonna be a pain in the arz if I have to unplug it in the middle of programmes every day or every other day to get the picture back!

Is it plugged in?

Funnily enough yes, although switching it off [waiting 5 mins] then on again does help :P

Share this post


Link to post
Share on other sites

I bought a 42" LCD for £25 recently, the volume is stuck on max

For that price, I couldn't turn it down

boom boom

tape a couple of cushions around your ears, that would drown out the sound a bit, plus the banging on the walls from the neighbours :)

Share this post


Link to post
Share on other sites

I have a TV with the scart socket hanging down and use a TV sender with a hard wired scart that seems a bit smaller than other scarts. So I used a scart adaptor for the one from the TV sender and then plugged the adaptor scart into the TV. Even then every time my partner dusted the TV cupboard and TV we would lose sound and/or picture.

I solved it by getting rid of my partner and now I don't dust :lol:

Share this post


Link to post
Share on other sites

So this fault only happens when you're trying to watch the picture coming from an external satellite receiver which is connected to the TV using an HDMI cable?

Trust me, HDMI leads are notorious for failing. Try a new one. Even if it's a cheap 'n chinkie £1.99 one from Ebay, just try it. I used to work in the cinema industry and have friends that still do. Since the conversion to digital projection, devices that connect to the d-cinema projector via HDMI have caused a world of pain. HDMI is theoretically capable of some stupidly high bandwidth - something like 10 gigabits IIRC. Most consumer HDMI applications don't use anything like that much (typically around 30 megabits for Bluray, for example). However, once you try to push the it towards the limit, dropouts start to happen. Add to that HDCP, and the error rate has to be very low, because of the computing power needed to decrypt the HDCP in real time. And the thing with a digital connection is that you either get a perfect picture, or nothing at all. For devices that connect using SDI (either single or dual link), this problem simply doesn't happen.

The thing about HDCP is that in most implementations, it only encrypts the video. So your audio not dropping out is consistent with an HDCP problem.

My guess would be that your HDMI lead can't handle seriously high bitrates. So the picture stream is arriving into the TV corrupted, and it can't do the error correction and decrypt the signal fast enough to show it: hence the black screen. If you try another cheap cable and the pattern of dropouts changes or goes away, you know you're on the right track. At that point, it might even be worth investing in a poncy, expensive HDMI connector.

Share this post


Link to post
Share on other sites

So this fault only happens when you're trying to watch the picture coming from an external satellite receiver which is connected to the TV using an HDMI cable?

Trust me, HDMI leads are notorious for failing. Try a new one. Even if it's a cheap 'n chinkie £1.99 one from Ebay, just try it. I used to work in the cinema industry and have friends that still do. Since the conversion to digital projection, devices that connect to the d-cinema projector via HDMI have caused a world of pain. HDMI is theoretically capable of some stupidly high bandwidth - something like 10 gigabits IIRC. Most consumer HDMI applications don't use anything like that much (typically around 30 megabits for Bluray, for example). However, once you try to push the it towards the limit, dropouts start to happen. Add to that HDCP, and the error rate has to be very low, because of the computing power needed to decrypt the HDCP in real time. And the thing with a digital connection is that you either get a perfect picture, or nothing at all. For devices that connect using SDI (either single or dual link), this problem simply doesn't happen.

The thing about HDCP is that in most implementations, it only encrypts the video. So your audio not dropping out is consistent with an HDCP problem.

My guess would be that your HDMI lead can't handle seriously high bitrates. So the picture stream is arriving into the TV corrupted, and it can't do the error correction and decrypt the signal fast enough to show it: hence the black screen. If you try another cheap cable and the pattern of dropouts changes or goes away, you know you're on the right track. At that point, it might even be worth investing in a poncy, expensive HDMI connector.

I (personally) believe that its a knackered screen...Dodgy HDMI cables (AFAIK) wouldn't cause the problems that the OP is suffering...

Share this post


Link to post
Share on other sites

So this fault only happens when you're trying to watch the picture coming from an external satellite receiver which is connected to the TV using an HDMI cable?

Trust me, HDMI leads are notorious for failing. Try a new one. Even if it's a cheap 'n chinkie £1.99 one from Ebay, just try it. I used to work in the cinema industry and have friends that still do. Since the conversion to digital projection, devices that connect to the d-cinema projector via HDMI have caused a world of pain. HDMI is theoretically capable of some stupidly high bandwidth - something like 10 gigabits IIRC. Most consumer HDMI applications don't use anything like that much (typically around 30 megabits for Bluray, for example). However, once you try to push the it towards the limit, dropouts start to happen. Add to that HDCP, and the error rate has to be very low, because of the computing power needed to decrypt the HDCP in real time. And the thing with a digital connection is that you either get a perfect picture, or nothing at all. For devices that connect using SDI (either single or dual link), this problem simply doesn't happen.

The thing about HDCP is that in most implementations, it only encrypts the video. So your audio not dropping out is consistent with an HDCP problem.

My guess would be that your HDMI lead can't handle seriously high bitrates. So the picture stream is arriving into the TV corrupted, and it can't do the error correction and decrypt the signal fast enough to show it: hence the black screen. If you try another cheap cable and the pattern of dropouts changes or goes away, you know you're on the right track. At that point, it might even be worth investing in a poncy, expensive HDMI connector.

Yes, so far only from the HD sat tuner. The TV is full HD too btw.

I know you're something of an expert on AV stuff and I appreciate what was for me a very interesting read about HDMI above. But, as DB says below, would a dodgy HDMI cable cause the screen to blank 100% so that even the TV's own Menu and other displays don't come on either? And of course, the other sources through other cables also don't display and the screen stays blank although you can hear the sound. If so, then what I guess you're saying is that a dodgy HDMI lead sort of 'trips' or confuses the TV's electronics and it loses the picture as a result of getting 'freaked out' by the bad HDMI lead or, as one IT man I used to know put it to me technically: 'the server's got its knickers in a twist'.

I (personally) believe that its a knackered screen...Dodgy HDMI cables (AFAIK) wouldn't cause the problems that the OP is suffering...

Does a knackered screen come and go like that, ie work for many hours then take a nap, then come back after an unplug of 5 mins?

Share this post


Link to post
Share on other sites

But, as DB says below, would a dodgy HDMI cable cause the screen to blank 100% so that even the TV's own Menu and other displays don't come on either? And of course, the other sources through other cables also don't display and the screen stays blank although you can hear the sound. If so, then what I guess you're saying is that a dodgy HDMI lead sort of 'trips' or confuses the TV's electronics and it loses the picture as a result of getting 'freaked out' by the bad HDMI lead or, as one IT man I used to know put it to me technically: 'the server's got its knickers in a twist'.

My guess would be that the onboard computing power in the telly is so preoccupied with trying to decrypt a bad HDCP stream that it locks up the whole thing. Same syndrome as when you have a 'not responding' program on a Windows PC, and even ctrl/alt/del has no effect until the operating system times out in its own sweet time.

Does a knackered screen come and go like that, ie work for many hours then take a nap, then come back after an unplug of 5 mins?

Unplugging it drains all the capacitors, clears all the memory ... in effect, it's a German reboot.

Suggestion: borrow another HDMI lead from a friend or relative, and see if that cures it. It'll cost you nothing.

The fact that the TV is only acting up when you're trying to watch a feed from this external device says to me that there's nothing wrong with the TV itself. If you were able to replicate the same fault when viewing video from more than one source, then I'd be suspecting the TV.

Share this post


Link to post
Share on other sites

My guess would be that the onboard computing power in the telly is so preoccupied with trying to decrypt a bad HDCP stream that it locks up the whole thing. Same syndrome as when you have a 'not responding' program on a Windows PC, and even ctrl/alt/del has no effect until the operating system times out in its own sweet time.

Unplugging it drains all the capacitors, clears all the memory ... in effect, it's a German reboot.

Suggestion: borrow another HDMI lead from a friend or relative, and see if that cures it. It'll cost you nothing.

The fact that the TV is only acting up when you're trying to watch a feed from this external device says to me that there's nothing wrong with the TV itself. If you were able to replicate the same fault when viewing video from more than one source, then I'd be suspecting the TV.

As HDMI carries audio and visual (and it was a dodgy cable), why would it only effect only the visual and not the audio? Send it back, but be prepared to wait 6-8 weeks for it to be fixed (if you bought it over 28 days ago, you might be able to get it exchanged (depending on who you bought it from)...

Share this post


Link to post
Share on other sites

As HDMI carries audio and visual (and it was a dodgy cable), why would it only effect only the visual and not the audio?

Because in all probability, only the video is HDCP-encrypted.

Share this post


Link to post
Share on other sites

Because in all probability, only the video is HDCP-encrypted.

To me, it sounds much more serious...although you do have to troubleshoot... Try streaming via DLNA (most modern TVs have it)...

Share this post


Link to post
Share on other sites

My guess would be that the onboard computing power in the telly is so preoccupied with trying to decrypt a bad HDCP stream that it locks up the whole thing. Same syndrome as when you have a 'not responding' program on a Windows PC, and even ctrl/alt/del has no effect until the operating system times out in its own sweet time.

Unplugging it drains all the capacitors, clears all the memory ... in effect, it's a German reboot.

Suggestion: borrow another HDMI lead from a friend or relative, and see if that cures it. It'll cost you nothing.

The fact that the TV is only acting up when you're trying to watch a feed from this external device says to me that there's nothing wrong with the TV itself. If you were able to replicate the same fault when viewing video from more than one source, then I'd be suspecting the TV.

I have reset the TV and will see how it goes now. Has gone 3 hours with no blanking again so far. The firmware looks like it is still the new one from Jan 2013. If it goes blank again (I know it very probably will) I will swap the HDMI cable over. It's a new HDMI cable anyway, but not an expensive one. It's supposed to be a quality brand but who knows.

I'll update the thread with whatever happens, thanks for the help TAB and all.

Share this post


Link to post
Share on other sites

I have reset the TV and will see how it goes now. Has gone 3 hours with no blanking again so far. The firmware looks like it is still the new one from Jan 2013. If it goes blank again (I know it very probably will) I will swap the HDMI cable over. It's a new HDMI cable anyway, but not an expensive one. It's supposed to be a quality brand but who knows.

I'll update the thread with whatever happens, thanks for the help TAB and all.

I know SMART can be an absolute bugger to update, and it can stop you using the TV, but it should give you an on screen prompt if its updating...

Share this post


Link to post
Share on other sites

I know SMART can be an absolute bugger to update, and it can stop you using the TV, but it should give you an on screen prompt if its updating...

Yes it does ask, and gives the usual warnings such as not to unplug the set while it updates, or it could become a brick :)

Did you get this telly from a well known supermarket ?

I'm not in the UK, but I think Sainsbury's was selling them a while ago. Is there a known problem with some Toshibas resulting in them getting discounted? It's got a fab picture when it works, be a real shame if it's a dud as not sure I can get another

It lost its picture again last night (4 hours on), even after the reset. I'm now checking to see if other sources also cause picture loss. If so, I imagine it's overheating in some way because I got the picture back last night by just putting it on standby for 5 mins, not unplugging it from the mains.

Share this post


Link to post
Share on other sites

Whenever I upgrade the firmware on my Samsung led it goes back to "shop mode" and loses the brightness settings etc after an hour. The only way to switch it back to home mode was through settings in the old analogue menu.

Might be worth a look to see if it doing a screen saver thing. Sky boxes have energy saving settings too.

Share this post


Link to post
Share on other sites

  • Recently Browsing   0 members

    No registered users viewing this page.

  • 243 Brexit, House prices and Summer 2020

    1. 1. Including the effects Brexit, where do you think average UK house prices will be relative to now in June 2020?


      • down 5% +
      • down 2.5%
      • Even
      • up 2.5%
      • up 5%



×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.