reaching out because I´m quite desperate regarding the problems we have regarding number presentation on incoming diverted calls, both national and international.
unify Openscape 4000 (our pbx)
Audiocodes 500 in SBC Mode (maintained by BT of course)
We cannot see the original callers number when a call diversion is enabled. For example, someone with number 123 calls our landline number 456, which is forwarded to another number 789. On the forward destination 789 device number presentation will be 456 instead of the original callers ID 123 so we just cannot see who is calling.
We tried to adjust SIP settings according to some of BT´s suggestions (PAI,PPI,Diversion Header) but still no chance.
Has anyone managed to get this to work and is willing to share the magic formula? Any help is much appreciated.
Many thanks in advance !