Jitter Buffer Settings

A jitter buffer is used at the receiving equipment to store incoming RTP packets, re-align them in terms of timing and check they are in the correct order. If some arrive slightly out-of-sequence then, provided it is large enough, the jitter buffer can put them back into the right sequence. However, for this to work the receiving device must delay the audio very slightly while it checks and reassembles the packet stream.

Jitter Buffer Settings

Go to Settings > PBX > General > Jitter Buffer to enable and configure jitter buffer settings.

Option Description
Enable Jitter Buffer Whether to enable jitter buffer.
Select which trunk(s) to enable Jitter Buffer Enable jitter buffer for the selected trunks.

The outbound audio through the selected trunk will be dejittered by jitter buffer on the other side.
Select which extension(s) to enable Jitter Buffer
  • Enable jitter buffer for the selected extensions.

    The received audio on the selected extension will be dejittered by jitter buffer.

    Note: In the following conditions, jitter buffer will not work for the selected extensions:
    • In an internal call, the audio is received from an analog phone or an IAX extension.
    • In an external call, the other side sends audio through a non-SIP trunk, and jitter buffer is not enabled for the trunk.
Implementation The implementation of jitter buffer.
  • Fixed: The length of jitter buffer will always be the sized defined by Jitter Buffer Size.
  • Adaptive: The length of jitter buffer will vary in size within the range of min size and max size based on current network condition.
Adaptive Adjustment Size The size of each adaptive adjustment of jitter buffer. The default is 50ms. If set by default, the jitter buffer size will be adjusted dynamically based on current network condition. It will start from 0 ms and grows at a size of 50 ms each time.
Max Jitter Buffer Size The maximum value of adaptive jitter buffer.