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You may get problems that audio sounds broken, this is generally caused by out of sequence packets.

With most systems this can be fixed by using either of these methods:

1) Enable Re-sequencing

Re-sequencing allows a little more time for packets to arrive. Please contact our support department to request we enable this feature.

2) Enable a Jitter Buffer

With FreePBX (Asterisk based Distro's like Trixbox, Elastix etc) you can change this in the sip_general_custom.conf

here are the variables you will require:

;Enable Jitter Settings
jitterbuffers=4
jbenable=yes
jbforce=yes
jbimpl=fixed
;jbimpl=adaptive
jbmaxsize=50
jbresyncthreshold=100
jblog=yes

Asterisk sip jbenable = yes|no
Enables the use of a jitterbuffer on the receiving side of a SIP channel. (Added in Version 1.4)

Asterisk sip jbforce = yes|no
Forces the use of a jitterbuffer on the receive side of a SIP channel. Defaults to "no". (Added in Version 1.4)

Asterisk sip jbmaxsize = Number
Max length of the jitterbuffer in milliseconds. (Added in Version 1.4)

Asterisk sip jbresyncthreshold = Number
Jump in the frame timestamps over which the jitterbuffer is resynchronized. Useful to improve the quality of the voice, with big jumps in/broken timestamps, usually sent from exotic devices and programs. Defaults to 1000. (Added in Version 1.4)

Asterisk sip jbimpl = fixed|adaptive
Jitterbuffer implementation, used on the receiving side of a SIP channel. Two implementations are currently available - "fixed" (with size always equals to jbmaxsize) and "adaptive" (with variable size). Defaults to fixed. (Added in Version 1.4)

Asterisk sip jblog = no|yes
Enables jitterbuffer frame logging. Defaults to "no". (Added in Version 1.4)

3) Utilise G729 Codec

The codec that you are using may be intolerant (G711 being a known example) of the disordered packets that are inevitable when using Sharedband. Please arrange for a more tolerant codec to be employed within your VOIP system. A known example of a more tolerant codec is G729.

4) Apply Line Prioritisation

Specific traffic can be prioritised by Sharedband using its 'Line Prioritisation' feature within these paramaters:

Priorised traffic must be directed thorough a single connection, this connection must be either node 1 or 2 and this connection must be designated

Prioritised capacity cannot exceed 95% of the total capacity available to this designated connection

To enable Line Prioritisation on the service, please provide the following values to us:

• Which connection you would like to designate for prioritised traffic
• What percentage of that connection's total capacity you would like to allocate for upstream prioritised traffic
• What percentage of that connection's total capacity you would like to allocate for downstream prioritised traffic
• Either the TOS, DSCP, or DS value of the traffic to be prioritised along with clarification of which of these values it is that you are providing