Who's to blame? the Sky HD box or my Denon 1906?


Standard Member
My Sky+ HD box is attached to my Panasonic plasma by an HDMI cable.
The Sky+ HD box is also attached to my Denon 1906 amp via an optical cable
When I watch the picture on the tv with the sound from the amp, the sound is delayed by a few frames. I can tell that by playing both the sound from the tv (from hdmi) and the amp (optical) and you can hear the delay.
Now, there's no use using the delay feature on the amp because it's already behind, not ahead, of the picture.
Nor is it worth adjusting the sound delay on the Sky box because that just puts it out of sync with the pictures.
So, is it that the Sky HD box sends audio faster through the hdmi cable than the optical one, or is the amp to blame because it take that delay to get the sound through it's system and out to the speakers.
Do all amps do this? should I upgrade to a HDMI system like the Denon 1910?
Your thoughts and solutions please.
many thanks


Active Member
The fact that you are separating the Audio and Video signals and processing them separately causes the delay. The TV and Amp will be processing the sound and picture independently and in differing amounts of time. This issue arises from the fact that Sky didn't include Digital Audio over HDMI for some bizarre reason on their HD boxes but you may also get this with other equipment where only the audio is being passed to the amp. If the amp was handling both audio/video on the same input it would keep them both in synch. Most AV Amps have an AV synch feature which will allow you to delay or speed up the sound for an assigned input in 1ms increments. This should allow you to get the sound and picture back in sync. I don't own this model so you will need to check the manual to find how to do this but I would be surprised if the option was not available.


Standard Member
Hi Coop
many thanks for the reply, what you say makes sense.
Unfortunately the amp only has an option to delay the audio, (which makes it further out of sync) rather than advance it.
I expect my only option would be to buy another amp which has HDMI inputs for video and audio, and route both through the amp, so as the pictures stay in sync. What are your thoughts on that?
Also, you mention Digital Audio over HDMI in your reply, is that some sort of priority system that the Sky HD box doesn't have?
thanks for you time


Distinguished Member
SkyHD boxes are notorious for this problem, with possibly different channels having a different delay indicating its possibly somewhere in the broadcast chain, so changing amp will probably not solve it.

The other problem you would run into if you intend to use HDMI from Sky for both audio and video, is that its only stereo over HDMI. Dolby Digital from SkyHD is only available from the optical (or digital coax) output of the box.

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