HDX 8000: Near-end Echo Issue

[Anonymous]

Good Day guys,

I have a polycom HDX 8000 that is experiencing Near-End echo( own site). It should also be good to let you guys know that my system is hooked up to a Polycom soundstructure C16 and that AEC settings have been appropriated. The far end's HDXs are simple systems; HDX 8000s with HDX mic array outputting to TV.  Their echo cancellation check boxes have been checked.

Here is the deal:

Not every far end site is able to replicate the issue. When I made an ISDN call to another test site, there is no problem. When I made a test call to my laptop (realpresence desktop), no echoes are heard. But when I made calls to 3 of my own companies'sites, I experience near end echo. I have checked the echo cancellation settings on all the far end HDXs and they are enabled. One particular thing to note is that these echo are not consistent, they only initiate after both I (near-end) and the other party (far end) speak together at the same time. The echoes start to come on and then, even as we stop talking together, and proceed to speak one person at a time, the echo will still prevail a while. The echoes are quite feint.

Has anyone of you come across this? I've tried swapping my unit of HDX with another, and problem persists. I have updated my C16 to the lastest firmware and problem persists. Could it be a network component issue that could be providing an infrequent loopback to my own codec? 

Thank you guys so much for your help.

[KK_Sky]

Hello,

Usually if I experience echo it is from a far-site that has its mic too close to the speaker (TV or ceiling) and then it will cause problems. I'm wondering what distance you are running from your speaker to your mics and if it is actually looping back trhough an unmuted far-site? Or, perhaps you may be hearing yourself back trough the far site unmuted and with the mic too close to their speaker? Only a guess, but might help...

[Anonymous]

Echo - your voice heard back almost exactly as spoken - is caused by the far end.  Your voice is coming into the far room and getting back into the that rooms mic.  So now the 'why' question. Typically there may be a delay in the incomming audio that exceeds the built in echo canceler.

With the Sound Strcture the HDX built in echo cancellation is not used. The SS echo cancel takes over.  There are many different configuration options on how the audio is routed through the SS. I suggest verifying proper configuration in the SS.