Hello MalcolmWallace,
welcome to the Polycom Community.
I believe Vodafone has done interoperability testing with our SoundStation units but I am not sure if this covers the UK.
I know other European Vodafone entities have launched these with a Vodafone branded design.
Oct 7, 2011 Question: Can I register or is my Polycom Phone compatible with a “XYZ” SIP Server?
Resolution: Please check => here<=
Usually the above details added in the Phone matching the Server SIP Details work for SIP compatible servers.
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