A friend of mine had this issue too, when he tried to run this "party-mode". The delay is about half a second. Very annoying. I thought it could be fixed with an update, but it wasn't. That was a few months ago...

HUGE issue with the sound delay. can be "fixed" by setting the time delay in BS3 to 0.  Enter service menu, choose monitor, sound adjustments, and set the sound delay to 0. After this, however the sound on your mainroom tv will not be in synch. So after the party, you will have to switch it back.

My dealer told me that B&O are working HARD on this issue and that a solution maybe is introduced with the new DVB-HD update in 4 days.

/Ehlerz

Don't even get me started on this.....

I have quite an open plan downstairs and the echo is unbearable! So in some respects, I feel I have gone backwards replacing my Avant with a BV10!

i feel the exact same way with my bv 7-32 bv 7-40 Mk IV tradeoff. SO embarrassing for B&O..

I have this issue, too. Turn the BV7-40 MKIV on in one room (open plan), move to the kitchen, turn on the BV8-26 and there's a clear audio delay on the BV8-26 :(

Is there any difference if the sound delay in the link room is transmitted via MasterLink or via RF (Antenna = Mono) cable?
And, if I want to listen to music (N.MUSIC) from my BM5 without any delay, then I turn on BM5 on my link tv (bv 8-32) and uses then MasterLink for the sound.
In the main room I do then select N.MUSIC on the bv 7, and then it is in Sync. But then I dont use the digital sound on the bv 7 (and the better picture quality to navigate on BM5).
But, my wife does not understand why it is such a big problem getting sound in Sync. So we also hope for something good from B&O.

I think there is a quick solution for this:

I have a Apple TV connected to my BS3 as V-Aux (both digital and analog wires connected) in my main room.

To get sound in every link room I press A-V.AUX in the particular room with the AppleTV playing music at the main room. Now you get  this annoying sound delay.

But now, if I press A-V.AUX in the main room as well, no sound delay anymore. I found this out by accident.... 

To get lip synchronisation the sound of BeoSystem 3 and all BSys 3 based TVs like 7-55, 7-40 (Mk3 & Mk4), all BV9-50 has to be delayed.
There are some workarounds to solve the "echo problem" with some tradeoffs like "AV" on the main TV (no surround, only stereo and loosing lip-sync) or setting the delay to zero (no lip-sync) ...

Since a few days a new software version to solve the "echo issue" for the previous mentioned models is available to dealers & service centres for updating existig equipment . But, be patient, details for the new function have not yet been released -  personally, I wouldn't like to be the guinea pig.

The (software) build is "only internally compatible" - meaning -  the complete software of the unit has to be updated to the same built!
B&O says, if an update adds a new feature (e.g. delaying of the ML output) to your unit, no warranty claims will be accepted (they don't refund anything to your dealer for his labour)

So be prepared to pay for this update ...