Audio Sync issues HDMI > Optical

Good Man · Joined: 01 Aug 2007 Posts: 1

LymanAlpha wrote in $yV6.33
@newssvr25.news.prodigy.net:

> Finally when I'm watching TV (I grab digital TV OTA, no cable or
> satellite) the optical digital out to the Yamaha is in sync with the TV
> speakers. This only occurs when using the 360 (doesn't matter what kind
> of media I'm playing on the 360 either, could be games, HD DVDs, mp3s
> etc...)
>
> Any hope of a fix? Or an explanation of what's happening...

I think what you're experiencing is the brief signal change from Dolby
Digital (or whatever your Xbox 360 audio signal is) to regular 2-channel
encoded audio, via your television.

As far as I know, televisions are required by copyright law to disable
Dolby Digital and other digital audio signal processing on the audio-out.
They can only send 2-channel audio via Optical/Coaxial audio out.

The loss of true digital audio when going from your game device -> tv ->
receiver is a common complaint, and the only solution is device -> receiver
for audio.

I'm guessing it's related to your problem in that your TV is taking
milliseconds to change the audio signal.

Archived from group: alt>tv>tech>hdtv

LymanAlpha · Joined: 23 Oct 2007 Posts: 1

I have a Toshiba HDTV (42HL67 3 HDMI inputs), XBox 360 (w/ HDMI out) w/
HD DVD Add-on and a Yamaha AV Receiver (two optical inputs, no HDMI). I
have my 360 connected to the Toshiba via HDMI. I have an optical cable
running directly from the 360 to the Yamaha and I also have an optical
out going from the TV to the Yamaha.
I should point out that my problem is not really a lip-sync problem, in
all cases the sound matches the video. If there is any difference it's
milliseconds and not noticeable. Where the synchronization issue arises
is between the sound outputted to the TV speakers and to the Surround
System. It's close enough that at first I simply thought it was the
result of a "sound field" effect the Yamaha can produce (e.g. slight
echo in a large room).
I can be rid of this issue by turning one of the speakers down but I'd
like to find another answer. The Yamaha has Audio delay capabilities,
unfortunately, the Yamaha source is the one that's delayed. What I need
is a delay on the TV sound.
This delay with the surround system occurs whether the sound is going
360>optical>Yamaha or if it's going 360>HDMI>Toshiba>optical>Yamaha.
It's worse in the latter case.
Finally when I'm watching TV (I grab digital TV OTA, no cable or
satellite) the optical digital out to the Yamaha is in sync with the TV
speakers. This only occurs when using the 360 (doesn't matter what kind
of media I'm playing on the 360 either, could be games, HD DVDs, mp3s
etc...)

Any hope of a fix? Or an explanation of what's happening...

Thanks.
--
"Out here on the perimeter there are no stars"

Steve --Inglo--

AZ Nomad · Joined: 01 Aug 2007 Posts: 165

On Tue, 23 Oct 2007 16:14:37 GMT, LymanAlpha wrote:

>I have a Toshiba HDTV (42HL67 3 HDMI inputs), XBox 360 (w/ HDMI out) w/
>HD DVD Add-on and a Yamaha AV Receiver (two optical inputs, no HDMI). I
>have my 360 connected to the Toshiba via HDMI. I have an optical cable
>running directly from the 360 to the Yamaha and I also have an optical
>out going from the TV to the Yamaha.
>I should point out that my problem is not really a lip-sync problem, in
>all cases the sound matches the video. If there is any difference it's
>milliseconds and not noticeable. Where the synchronization issue arises
>is between the sound outputted to the TV speakers and to the Surround
turn the tv speakers off.

steveo · Joined: 28 Nov 2007 Posts: 1

wrote in message @w34g2000hsg.googlegroups.com...

> I suppose a solution would be to buy a receiver with HDMI
> input?

Only if it is NOT a pass-through HDMI port. Pass-through does not process
audio, it just, as the name declares, passes through the signal. On those
types of A/V receivers, you need to send the audio to the AVR via another
connection (typically coax or optical).

steveo