OT: Sync/drift audio issues while programs are Broadcast

Hi all,

A client of mine is having problems with some of their programming being as much as 3 seconds out of sync while it is being aired.

The funny thing is not all cable/satellite providers are experiencing the audio drift.

Of course everyone is pointing the proverbial finger at everyone else.

Here is what is known:

All programming leave a post facility in Atlanta to the uplink facility with no problems whatsoever.

The uplink facility monitors the programming and of course no reported problems.
Some cable/satellite providers receive the satellite signal and feed it to their subscribers and lo and behold audio sync issues and others are not reporting any problems at all.

The workflow, as best as I understand is this:

DVCPRO HD to the uplink facility.
Mpeg 4 compression up to satellite
Mpeg 4 compressed signal recieved at providers

Now here is the wrinkle:
Some providers use Mpeg 4 compression
Some use Mpeg 2
Some downconvert the HD signal Some only provide the channel in HD.

And of course not everyone is using the same distribution equipment to get the channel into the homes.

I personally think there is a firmware issue with some of the providers distribution equipment.
I also think there is so much compression on top of compression that resolving this might work for some and not for others.

I am glad it is not my nightmare, but I could become a savior to client.

I welcome any and all thoughts.

Barry

When I worked for the local FOX affiliate in San Diego, we would experience audio sync issues in some of our programming. The issue ended up being the encoders that compressed the signal down the line. The video would get behind, but the audio would fly on through.

But also, services like Direct TV got our programming from our Time/Warner signal, and sometimes there would be problems in the transfer of the signal, so Direct TV subscribers would have issues, but not cable houses.

Bottom line is it could be a lot of things, and they're all on the broadcast end. Just be glad that the sync is correct on the tape or file you upload.

Andy

frames here & there but I can't think of anything in my experience that would account for a discrepancy of up to 90 frames. Presumably the broadcasters are not just passing the sat signal through in real time as they receive it, they are storing & forwarding, correct? If this is the case, I blame that part of the chain, because humans & older gear are probably involved. 3 seconds is still a lot though.

Guys,

Thanks for your input. It is much appreciated.

The problem is mainly with Time Warner and Dish Network.
I know Dish is storing it before forwarding the sat signal.
My guess Time Warner is as well.

Funny enough, those two outlets were the most recent additions to carry the channel.