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Polycom VVX - payload size not included in SDP offers

Occasional Advisor

Polycom VVX - payload size not included in SDP offers

I have this problem with all my VVX phones (VVX 500 and VVX 1500). The "ptime" parameter is not included in SDP offers.


I have attached a .cfg file showing that g722's ptime is set to 40 and a wireshark trace for an outbound g722 call which shows that the SDP offer does not include the "ptime" parameter.


UC Software Version:

Polycom Employee & Community Manager

Re: Polycom VVX - payload size not included in SDP offers

Hello @nmadani ,


welcome back to the Poly Community.

Not sure this really needed a new post as you posted this already => here <=.


The software version used is no longer supported so please test 6.0.0 if compatible with your yet  model or 5.9.2


Alternatively, you could try a later 5.6.x software.


If this fails the next step is a support ticket.

In order to raise a support ticket you need to work with your Poly reseller as they need to do this for you.

End Customers are unable to open a ticket directly with Poly support.

If this is some sort of an Internet discounter providing your MAC address or your Poly devices serial will enable us to look up who would be able to support you. This may not be who you purchased the Poly device from.

If the unit is no longer within the warranty please be prepared to Pay Per Incident / PPI. This is all outlined in detail here

Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.

Best Regards

Steffen Baier

The title Polycom Employee & Community Manager is a community setting and does not reflect my role. I am just a simple volunteer in the community like everybody else. All posts and words are my own & do not represent the views of Employer.


Notice: This community forum is not an official Poly support resource, thus responses from Poly employees, partners, and customers alike are best-effort in attempts to share learned knowledge. If you need immediate and/or official assistance please open a service ticket through your proper support channels.
Please also ensure you always check the VoIP , Video Endpoint , Skype for Business , PSTN or RPM FAQ's
Message 2 of 3
Occasional Advisor

Re: Polycom VVX - payload size not included in SDP offers

Hello Steffen,


Thank you for your response. I was not getting any help on the previous post so I created a new one. Sorry about that.


I upgraded to 5.9.2 and the issue persists. Based on Polycom documentation the "voice.audioProfile.x.payloadSize" attribute can be set to "10, 20, 30, ...80" and this should change the "Preferred Tx payload size in milliseconds to be provided in SDP offers and used in the absence of ptime negotiations". 


But there is no "ptime" in SDP offers to be changed. I have this issue with all Polycom VVX phones. Could you please verify if you or anyone you know of can actually see the "ptime" in SDP offers?


Thank you.

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