Cisco 2811 as CUBE SIP2SIP gateway to a SIP provider. Behind CUBE a bunch of CME all connected to the CUBE through SIP. Works great.
Started with UCM7 connecting through a SIP trunk to CUBE. Call setup works but about 50% of the outbound calls (inbound works all the time) fail due to RTP issues ( I think ). Caller then hears a continues tone which eventually stops.
Tried all kind of scenario's. Different codecs, hardware MTP, with or without MTP, h323 gateway etc.
What is see in the traces on the CUBE that when a call fails I see that it tries to reuse an (or the) existing RTP stream. When it does that the call fails. After the second, third or fourth time the call in reinitiated and when it sets up a new RTP stream is works out ok.
Any thought regarding timers and why the UCM behaves differently then the CME?