Solution
When at least one person in a call does not receive audio, IP connectivity between phones is not established.
Check the configuration of routers and switches to ensure that IP connectivity is properly configured.
General Telephone Call Problems
The following sections help troubleshoot general telephone call problems.
VPN-Connected Phone Does Not Log Calls
Problem
A remote location (home office) phone that is connected through the VPN does not log missed, placed, or
received calls.
Cause
Without explicitly setting the Alternate TFTP setting, the Cisco IP Phone cannot contact the TFTP server and
download the configuration and other files, and function properly.
Solution
Set up the phone to use the Alternate TFTP server and configure the TFTP server IP address.
Related Topics
Set Up Remote Phone, on page 222
Phone Does Not Recognize DTMF Digits or Digits Are Delayed
Problem
The user complains that numbers are missed or delayed when the keypad is used.
Cause
Pressing the keys too quickly can result in missed or delayed digits.
Solution
Keys should not be pressed rapidly.
Phone Call Cannot Be Established
Problem
A user complains about not being able to make a call.
Cisco Unified IP Phone 7941G, 7941G-GE, 7942G, 7961G, 7961G-GE, and 7962G Administration Guide for Cisco Unified
Communications Manager 9.0 (SCCP and SIP)
221
Troubleshooting and Maintenance
General Telephone Call Problems