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AndreasEK
02-29-2012, 09:52 PM
Hi,

my problem is that I cannot get audio and video to sync, when using my AVR.

TV: 55PFL7606K/02
AVR: Denpn AVR 1612
Connected via a HDMI 1.4 compatible cable. Both are running on the latest firmware.

TV configuration: EasyLink is turned on
AVR: LipSync option is turned on

I am using the TV to watch cable tv, so the audio is sent to the AVR via HDMI/ARC. The delay between audio and video is approx. 100ms (whith video coming first!).

My questions:
1) In my TV I have the option "Tonverszögerung" (audio delay) which I cannot find documented anywhere. Is that a gerenal audio delay, or is that option turning on the hdmi/lipsync feature?
2) When I switch off lipsync in my AVR, the delay is getting MUCH better. Can it be, that the TV is sending wrong delay information?

Thanks for your help, this is greatly appreciated.
Andreas

Philips - Thomas
03-01-2012, 06:43 AM
Hi

In your Case:
Turn off Lip Sync on both, TV and AVR.
The TV will then always send out Audio/Video Synchronized Data.

Sync turned on on the TV means that the TV will delay the audio dynamically based on the Video content.
Point here is that the connected Audio System needs to understand the cec control signals and must be able to compensate this dynamic data.

Sync turned on on the AVR means that this AVR will delay the Sound + the delay that comes with the original Signal, so that Option is nothing for you.
You would need that feature if the Video Source is not the TV but a external Receiver, connected via HDMI to the Receiver first and then to the TV.

Regards
Thomas

AndreasEK
03-01-2012, 12:44 PM
Hi Thomas,

thanks for your reply.



Turn off Lip Sync on both, TV and AVR.
The TV will then always send out Audio/Video Synchronized Data.


Is that the undocumented option "Tonverzögerung" on my Philips TV? When I turn off lip sync on my Denon AVR, the delay get's noticeably decreased. I have the suspicion that the Philips TV is sending out wrong (too high) lip sync data.



Sync turned on on the TV means that the TV will delay the audio dynamically based on the Video content.
Point here is that the connected Audio System needs to understand the cec control signals and must be able to compensate this dynamic data.

Sync turned on on the AVR means that this AVR will delay the Sound + the delay that comes with the original Signal, so that Option is nothing for you.
You would need that feature if the Video Source is not the TV but a external Receiver, connected via HDMI to the Receiver first and then to the TV.


According to hdmi.org, having lipsync active also for audio on the ARC should work without problems, in fact it is intended to be used like this (http://www.hdmi.org/manufacturer/hdmi_1_4/hdmi_1_4_faq.aspx#16):


Is the HDMI LipSync feature compatible with the Audio Return Channel?
Yes. Whether the TV is sending audio to the sound system or vice-versa, devices featuring LipSync functionality (introduced in HDMI 1.3) will be able to track and correct for any processor lags, and adjust the delivery of audio and video so that the two signals stay in sync.

So apparently, one of the two devices is doing it wrong. Either the Philips TV or the Denon AVR.

Philips - Thomas
03-01-2012, 01:59 PM
Hi

like i wrote above, to get synchronized Data Streams out of the TV you need to disable "Tonverzögerung" on the TV.
The TV will now check internally to have the Picture and Sound output synchronized. The TV does not care about any lag on AVR Side.
Most of the Time, the Sound then is behind the Picture.

If that Feature is on the TV will try to connect with the AVR via HDMI and check up speed of handling processes on AVR Side.
Means if the AVR send Signals that the AVR needs f.e. 50ms on certain Settings, the TV will give out the Audio 50ms before the actual Picture is shown.
But with respect to the TV Processing itself this is a constant dynamic Process. TV and AVR need to adjust this connect every ms and this is not supported by every AVR.

Regards
Thomas

AndreasEK
03-02-2012, 12:03 AM
Hi Thomas,

thanks again for the reply. So in summary that means that it SHOULD work with the TV set to "Tonverzögerung" and the AVR set to "Lipsync", but not all AVRs support that. As a workaround I can disable the options in both the TV and the AVR and get only a slightly delayed audio signal via the AVR.

Andreas

Philips - Thomas
03-02-2012, 06:39 AM
Hi



so in summary that means that it SHOULD work with the TV set to "Tonverzögerung" and the AVR set to "Lipsync"


...



Turn off Lip Sync on both, TV and AVR.
The TV will then always send out Audio/Video Synchronized Data.




like i wrote above, to get synchronized Data Streams out of the TV you need to disable "Tonverzögerung" on the TV.


...

Regards
Thomas