[Dave A]

I get to deal with this mess everyday in my career in broadcasting. What you are seeing is the variables of MPEG transmission as broadcasting rushes headlong in to digital.

So many broadcast plants, remote truck transmissions, news uplinks, et al are digital in one form of MPEG or another. With a few frame syncs thrown in along the line to get it back to analog. And that is just transmission. Origination at the station is from a server for the most part. Wheel of Fortune is just a server file. Edited on a computer. MPEG again.

With MPEG, everything is motion. The the more motion, the more the processing, the bigger the file/frame, the more the bandwidth, the more the pic slows down in relation to the audio. Eventually it catches up.

And then there are the converter boxes that are being used to get separate digital SDI (Serial Data Interface...which is the standard digital signal used in normal 4x3 transmissions or 16x9 lo def) video and analog audio combined to one data stream. Hi Def is another monster using 270 meg transmission.

I had a problem tonight with a black box from a long-haul transmission service that came to me with the audio wired out of phase.

You could have a news report from a landslide in Cali that goes;

Analog 4x3 camera to digital satellite uplink
Digital downlink to long-haul digital fiber transmission to studio
Digital switching in studio
Digital or analog uplink to satellite for distribution
Digital or analog downlink at cable headend or local station
Local digital conversion and TX for over-the-air 8VSB transmission or
Digital conversion to QAM 256 for digital cable box at home
Digital processing in your home plasma set

Add a few layers for transmission from overseas.

Just watch a NFL game and watch the processing try to keep up with a fast-moving deep pass on the wide shot, game coverage. StutterVision. Some networks are better than others. You can see it on any old beast that we all love. And that signal is a down-converted version that we call a "center cut" (4x3 analog from the Hi Def 16x9, 270 meg, digital original) version of the highly touted Hi Def original from the stadium. Another conversion which can be done at the origin or at the end transmission.

And different Hi Def plasma set mfrs have different processing in their sets. It pays to shop and compare. Watch out for sale sets. Older processors just like a cheap computer.

There will be a test later,

Dave A