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Modern 'smart' tellies these days often provide no analogue audio output for you to connect to a hi-fi system to improve the sound quality. Even when they do, it is often not synchronised very well to the video, usually coming a fraction of a second early.

Many provide an optical 'toslink' output only. A converter to conventional hi-fi audio will cost you five to ten pounds. This too is unlikely to be synchronised with the video.

To cure the problem you will need a lip-sync corrector which adds an adjustable delay to the audio. These cost around £50.

So if you are thinking of getting a smart telly and intend to connect it to a better audio system, its worth checking that what comes out is electrical rather than optical and properly synchronised to the audio. It is VERY distracting when the two are not synchronised.

Hopefully this will save someone the extra expense and hassle buying a smart telly has involved me in!

I have a wax model of the designer of my telly into which I shall insert pins! Grrr!

Thanks for that useful info. Certainly not something I'd have thought of.

Just a side note :

This is probably ref to smart TV apps like bbci player and such.

Where as you would not have the issue if you connected via say a sky or virgin box for the output.

Optical is becoming a more common connection nower days. You can get sound bars from about £100

But it is worth doing your homework as out of sync is like a dripping tap.

To be fair, it may be that the optical output appearing early is deliberate; designed to interface with amplifiers which accept it directly, and take a little time to effect the conversion.

The toslink data format is quite complicated and inevitably involves a delay before the digital to analogue conversion that follows its decoding.

My remarks apply only to conventional amplifiers which accept an electrical signal and produce an electrical output to speakers with negligible delay.

I was pleasantly surprised at how little the optical to analogue converter box cost, but horrified at the cost of the lip-sync converter. Of the two, I would have thought the lip-sync unit the simpler of the two in terms of its function and the amount of hardware involved.

But if you are looking at getting a smart telly, be clear about what you wish to connect it to, and make sure it is compatible.

On a related matter, I have a number of radio controlled clocks - and a radio controlled wrist watch which are spot on of course, and am amused to hear from TV and DAB radio if both are on and in hearing distance, a series of variously delayed repeats of the pips or Big Ben coming a second or two later than they should.

I guess its progress, but it sounds chaotic to me!

Got my little delay unit today. This delays the stereo signal by any amount up to 300 milliseconds, which you set with a little knob. In my case about 100 milliseconds did the job just right.

Took about five minutes to set up, and I can now forget its there, and enjoy the crap that passes for entertainment on the telly these days.