In my experience, 98% of the time this is a routing issue. Can you attach a network and call flow diagram? Are you running a flat network or is voice on a seperate VLAN? Are these issues happening locally or with remote locations? Are they happening between Cisco endpoints only or with external callers not associated with your system? Are you using site-to-site VPN tunnels over the Internet to connect remote locations or MPLS?
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.