Panasonic TV sound sync

I've just bought a Panasonic TX-L32ET5B TV from John Lewis. As the sound from the internal speakers is predictably poor I've hooked it up to my hi-fi (stereo only, not surround).
Connecting via optical cable into my DAC, the sound is slightly in advance of the picture, confirmed by the echo from the TV speakers. This is not confined to any particular channel, it happens across the board so the fault must lie with the TV. If I connect from the headphone socket it's OK.
The same thing happens with both electrical and optical outputs to the hi-fi from my Panasonic DMR-HW220 HDD recorder, but that can be corrected using the Audio Delay control.
As far as I can see (but please correct me if I've missed it) the TV doesn't have an audio delay control.
Is this a fault with this particular TV that warrants exchanging it for another, or is it just another aspect of progress that I'll have to get used to?
I suppose it's only a slight annoyance because I can just continue with the headphone output, but it is annoying to spend good money for something that doesn't work perfectly, for whatever reason.

Comments

  • Nigel GoodwinNigel Goodwin Posts: 58,328
    Forum Member
    I've just bought a Panasonic TX-L32ET5B TV from John Lewis. As the sound from the internal speakers is predictably poor I've hooked it up to my hi-fi (stereo only, not surround).
    Connecting via optical cable into my DAC, the sound is slightly in advance of the picture, confirmed by the echo from the TV speakers. This is not confined to any particular channel, it happens across the board so the fault must lie with the TV. If I connect from the headphone socket it's OK.
    The same thing happens with both electrical and optical outputs to the hi-fi from my Panasonic DMR-HW220 HDD recorder, but that can be corrected using the Audio Delay control.
    As far as I can see (but please correct me if I've missed it) the TV doesn't have an audio delay control.
    Is this a fault with this particular TV that warrants exchanging it for another, or is it just another aspect of progress that I'll have to get used to?
    I suppose it's only a slight annoyance because I can just continue with the headphone output, but it is annoying to spend good money for something that doesn't work perfectly, for whatever reason.

    The sound system you connect to should have audio delay settings - but as it's not a real surround sound system it probably doesn't?.

    It's NOT a fault with the TV, it's a fault of (not with) your audio system.

    Simply use the headphone output - there's no advantage using the optical out, as it's only stereo anyway.
  • iangradiangrad Posts: 813
    Forum Member
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    OP your new TV has ( Like most new tv's ) a dedicated HDMI connector ( HDMI 2 ) that has audio return on it but it relies on the sound system being reasonably modern ! Never any sync issues them .

    Might be worth investing in a sound bar or home cinema kit , virtualy unheard of to use optical in modern kit .
  • [Deleted User][Deleted User] Posts: 10
    Forum Member
    I phoned Panasonic (Indian call centre by the sound of it) and was told there is probably a fault with the optical cable causing the delay. I'm not convinced this is possible but am I wrong?
    Buying a surround sound system or sound bar may be an answer but not one I'm happy with because I don't want yet more expense. I just want better sound than the TV speakers provide. I already have a high quality stereo system which is all I need.
    If there is a technical reason why feeding digital audio through a DAC can lead to a sync problem I think Panasonic should make this clear. The fact that my kitchen TV, a Panasonic TX-L19X5B, has SPDIF delay adjustment in the sound settings menu proves that they know this happens, so why not include the adjustment across their range of TVs? Or stop providing an optical output if it's not needed with modern audio equipment and doesn't work with older systems.
    Anyway, as you say, I'll use the headphone output until such time as I feel the need for a new amp. with HDMI connections.
  • Nigel GoodwinNigel Goodwin Posts: 58,328
    Forum Member
    I phoned Panasonic (Indian call centre by the sound of it) and was told there is probably a fault with the optical cable causing the delay. I'm not convinced this is possible but am I wrong?

    No you're not wrong - it was a typical idiot Indian call centre worker.
  • gomezzgomezz Posts: 44,504
    Forum Member
    Does not the DAC have an audio-delay setting?
  • [Deleted User][Deleted User] Posts: 10
    Forum Member
    No, it's an old Audio Alchemy Digital Decoding Engine designed for hi-fi use. I bought it to convert the digital output from a CD transport.
  • late8late8 Posts: 7,175
    Forum Member
    No, it's an old Audio Alchemy Digital Decoding Engine designed for hi-fi use. I bought it to convert the digital output from a CD transport.

    My Panasonic gt50 is hooked up to a home cinema amp via optical. It too had sound delay problems at first but it was down to extra picture processing options like Intelligent frame correction etc. see if you can turn unnecessary options of or down like that.

    Also my amp has a lip sync setting too.
    If your system has nothing like this then there's nothing you can do.


    The echo from your TV speakers and separate speakers can't be relied upon. Your TV may have its own lip sync setting for its sound system. If this is behind or infront it may cause the echo.

    Does the sound from your separate system link up with the video?

    A good test is on BBC HD Previes that runs in the mornings. They have a sound test that shows delay.
  • [Deleted User][Deleted User] Posts: 10
    Forum Member
    I turned off IFC but it made no difference. Without sync settings on TV or amp I don't think there's anything I can do.

    I'll try the test card to set up the picture though, if I can find it, thanks.
  • late8late8 Posts: 7,175
    Forum Member
    I turned off IFC but it made no difference. Without sync settings on TV or amp I don't think there's anything I can do.

    I'll try the test card to set up the picture though, if I can find it, thanks.

    I think it may just be down to the amps processing. The BBC test will confirm if the sound is behind or infront.

    Have you tried using a analogue connection? Your TV might have coax L and R audio out or headphone out. Sometimes analogue can be more in sync.

    Does it look like the audio is behind? Eg lip sync. + have you turned the TV right down so you get amp only?
  • [Deleted User][Deleted User] Posts: 10
    Forum Member
    Sound via optical is ahead of video. Sound from headphone output is in sync. There are no analogue phono outputs, which would be more use than an optical output which isn't needed for modern equipment with HDMI connectors and doesn't suit older equipment without delay compensation. I suppose that's progress.
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