Cisco CallManager uses an interdigit timer to allow users sufficient time to enter the digits required to place their call.
For Cisco CallManagers in North America making use of the @ macro in their route patterns, the simplest solution is to use a route filter.
To resolve this issue, modify the default seven digit route filter.
Perform these steps:
If you are not making use of the @ macro in your dialing plan, you can shorten the interdigit timer value by referring to Delay in Call Establishment: Configuring the Interdigit Timeout.
If the delay is observed for on-net calls (such as calls between IP phones within a Cisco CallManager cluster), refer to User experiences a delay in call initiation when making local calls.
For more information, refer to Cisco 7900 Series IP Phones: Q&A.
After last digit is dialed
Placing local call