Siemens Gigaset C450

[elbatech]

I have a system with 3cx PBX phones Grandstream B200 and cordless Gigaset C450 IP.
I can not switch telephone calls from C450 to Grandstream.

Can you help?

 

[otaku-oni]

Transfers are a bit of hairy issue. Especially when every manufacturer seems to implement SIP behaviour as they will. Unfortunatley you seem to be running on devices that are not in the recomended list.

First thing to do is update those firmwares. Especially on the B200. If the problem persists use the Verbose logging feature, the SIP conversation in the logs might shed some light on your problem.

 

[archie]

Otaku-oni is perfectly right. But still you can try "Bind to media server" and disabling "support re-invite" to improve the situation.