I went out to dbstalk.com and apparently this is a huge and widespread issue - lots of threads deal with this. The audio is ahead of the video on most HD channels. Sounds like a problem with HD no matter the source - directv, dish, FIOS, etc all have this problem. Here is a quote from that forum:
"The problem is not necesarily DirecTVs to fix, although DirecTV has its part to play. You will see similar posts about audio-video sync on dish, digital cable and FIOS forums, and on forums discussing both hi-def DVDs and video processing in general. If you do a google search on A/V sync TV, you will find lots of references, including this
http://en.wikipedia.org/wiki/A/V_sync and this
http://tvtech.com/pages/s.0076/t.1814.html
And a quote this year from the Director of Engineering at Iowa Public Television;
QUOTE There are actually engineering working groups (I am on several of them) that are working within the industry to create a set of standards and recommended practices to address this issue. A/V sync problems have been around for decades, but in the past, the audio usually lagged behind the video and our brains are accustomed to seeing something and then hearing the sound because in nature, sound travels slower than light and we have adapted to that. Most of the time in DTV, the sound is ahead of the video and that is very unnatural and it doesn't have to be very far off for us to notice. We are currently in the process of renovating our production facility for HD production and we are giving exceptional attention to insuring that audio and video signals travel through are systems in sync. This is not to say there won't be problems but we are working dilligently to correct them. UNQUOTE
The problem is that even if the audio and video are synced correctly at the source (and often they are not), with digital signals the audio and video are not tied together through the various stages of transmission, reception and display. Every time the digital video and audio goes through any processing , the data accumulates in queues and buffers and all these cause delays, and they are different for audio and video. This buffering, particularly of video, happens at the station, in the distribution system between the station and DirecTV, in DirecTVs transmission system, the satellite, the DirecTV receiver and the TV itself. Some TVs are notorious for adding as much as a second of delay to the video. And the delays in HD are much worse than in SD because of the large amount of data.
There is no easy fix for this, especially since the delays involved in your equipment setup will be different from mine, that's one reason why some people see poor A/V sync and others watching the same channel don't..
The TV stations/channels are getting better at anticipating what the delays might be (and for those channels new to HD, there will be a learning curve). There are new proposals for adding data to the audio stream so that the audio and video can be synced later in the process. Some A/V receivers allow you to adjust the audio/video sync, you can also buy add-on boxes to adjust A/V sync ($500 or so). And the latest release of HDMI, HDMI 1.3, has A/V sync adjustment capabilities using an interface between the TV and the A/V receiver..
DirecTV can contribute to improving A/V sync by reducing the amount of buffering in the various stages of processing. The H20 and HR20 buffering, including the MPEG-4 decoders, can become more efficient. But I don't see a complete solution to this problem without introducing some changes in the way audio and video are handled through the processing chain."
Now tell me again how HD is supposed to be better than SD? At least SD knew how to make sure the audio was synced with the video! Wouldn't that be a basic requirement?
Quote:
Originally Posted by
jvcarig 
I have an older Sony AVR (10 years old) and I don't think I have this ability. There is a setting for "screen depth" but I can't figure out what that does. The reason I thought this was an issue/setting with the HR21 is because I have the same setup wth my PS3 (HDMI to TV, optical to AVR) and I don't have this issue. Sound and video are perfectly synced.