I have Cisco Unity 11.5 configured via sip to a CUCM v14. I have configured voicemail and everything works as expected except for one thing, when users press voicemail on their phone there is a long pause (10 seconds) before Unity will start playing ...

I stood up two Cisco 4331 ISR devices as CUBE with Box to Box redundancy / High Availability in accordance with the document linked below. Cisco Unified Border Element Configuration Guide Through Cisco IOS XE 17.5 - High Availability on Cisco 4000 Se...