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Dead air with PC>vvx300>switch


Dead air with PC>vvx300>switch

Awhile back i had switched about 12 polycom vvx300 phones over to a single switch and plugged the PCs into the vvx300s to limit the amount of ports used on the switch. However after doing so, whenever a user received a call the line would have a silence. no one would be able to hear each other (dead air). i ensured that ports 2222-2269 were open on the firewall. Is there a checklist or guide that i can access to show detailed steps and requirements to make that type of setup work?


Currently i switched everything back to the way it was and is now functioning. pc to switch and vvx300 to its own switch.

Message 1 of 4
Polycom Employee & Community Manager

Re: Dead air with PC>vvx300>switch

Hello Elix3r,

welcome to the Polycom Community.

It is always useful to include the currently used UC Software version as issues experienced may already be addressed in a newer release.

Please also include if you are using a SIP server or a LYNC server

If LYNC or Skype please provide Version details and if these are on premise of off premise

This also allows yourself and others to check against current software release notes.

The above is also stated in the "Read First: Welcome to the Polycom VoIP Forum"

Therefore the Polycom VoIP FAQ contains this post here:

Question: How can I find out my SIP UC Software Version or the BootROM Version of my Phone?
Resolution: Please check here




Jan 19, 2012 Question: How to troubleshoot Polycom VoIP related Issues?

Resolution: Please check => 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

Polycom Global Services


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 4

Re: Dead air with PC>vvx300>switch

Label: SIP




 Boot Block:

Message 3 of 4
Valued Contributor

Re: Dead air with PC>vvx300>switch


It sounds like the switch you moved the phones onto is half duplex, and as a result the audio stream will be cut out when there is any sound on your end, and the phone is uploading it. Try leaving the phones on the working switch where they are, and moving the PCs to the PCs port on the phones.

Message 4 of 4