This is on CUCM 8.6, the DN in question is a DID from a SIP provider terminated on a 2811CUBE (not sure of that is pertinent).
When I call the DID, it rings on phones that have that have that DN assigned to. But I can not answer the call. It will stop ringing on the receving phone when the handset is picked up, but there is no audio path. The phone that is calling that DID/DN keeps on ringing.
Although internal CUCM extensions/DNs work okay.
Anyone know what's going on? Thanks.