Hello Christian ,
welcome to the Polycom Community.
The SPIP550 should be on UC Software 4.0.11 and not 4.1.1 as this is for LYNC only.
I suggest you post your configuration and try and get some logs of the VVX Phone.
- Settings > Logging > Global Log Level Limit > Debug
- Settings > Logging > Log File Size (Kbytes) > 160
- Settings > Logging > Module Log Level Limits > SIP > Debug
- Settings > Logging > Module Log Level Limits > TLS > Debug
- Settings > Logging > Module Log Level Limits > CURL > Debug
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
