One way audio with g729

Discussion in 'General' started by jandir, Oct 15, 2008.

  1. jandir

    Joined:
    Aug 24, 2008
    Messages:
    65
    Likes Received:
    0
    Let me describe my setup first.

    I have two incoming sip trunks (IPKall and ViaTalk) and one zap trunk.
    IPKall is setup for g729 and ViaTalk uses g711u.
    I have two ATAs AC-211SR and Innomedia, both from Sunrocket, setup as extensions.
    Innomedia is configured for G711 and AC211 is configured for g729.
    I have installed g729 coded as per Elastix Without Tears and it works as far as I can tell.

    Here is the Problem.

    Incoming call on IPKall rings both ATAs (ring group). If I pick up from AC-211 there is no audio from AC211 to the caller audio other way works fine. If I pick up the incoming call from the Innomedia then audio both ways is fine. If I change AC211 to use G711 then audio is fine.

    Outgoing calls from innomedia and AC211 work fine through Viatalk (and Gizmo5).

    I have not tried incoming calls from Viatalk and Zap yet. Will update once I try it out. I have also not tried changing the Innomedia to g729.

    I need to get the AC211 working with g729 to be able to use it internationally as an extension.

    How do I debug this?
     
  2. jandir

    Joined:
    Aug 24, 2008
    Messages:
    65
    Likes Received:
    0
    I think I have solved the problem but am not sure of the root cause.

    Silence suppression in my ATA was set to on for g729. When I set it to off the audio problem goes away.

    When the call came in from IPKall the SDP showed silence suppression to be off, so maybe the mismatch between IPKall and the ATA caused some issue.

    Any explanations?
     
  3. alang

    Joined:
    Mar 19, 2008
    Messages:
    47
    Likes Received:
    0
    As far as I know the G.729 codec doesn't support silence suppression(or called VAD), so in most cases you should turn off this feature if the primary codec you prefer is g729.
     

Share This Page