Troubleshooting Tips; Where To Go For More Troubleshooting Information - Cisco 7965G Administration Manual

Chapter 9 Troubleshooting and Maintenance

Troubleshooting Tips

When you observe significant and persistent changes to metrics, use
troubleshooting information:
Table 9-5
Metric Change
MOS LQK scores
decrease significantly
MOS LQK scores
decrease significantly
Conceal Ratio and
Conceal Seconds
increase significantly
Conceal Ratio is near or
at zero, but the voice
quality is poor.
Note Voice quality metrics do not account for noise or distortion, only frame loss.

Where to Go for More Troubleshooting Information

If you have additional questions about troubleshooting the Cisco Unified IP Phones, several Cisco.com
web sites can provide you with more tips. Choose from the sites available for your access level.
•
OL-12650-01
Changes to Voice Quality Metrics
Condition
Network impairment from packet loss or high jitter:
•
•
Cross-check with Conceal Ratio and Conceal
Seconds for evidence of packet loss and jitter.
•
•
•
•
•
•
Check packet transmit (TxCnt) and packet receive
(RxCnt) counters to verify that voice packets are
flowing.
Cisco Unified IP Phone Troubleshooting Resources:
http://www.cisco.com/en/US/products/hw/phones/ps379/tsd_products_
support_series_home.html
Cisco Unified IP Phone 7965G and 7945G Administration Guide for Cisco Unified Communications Manager 6.0
Average MOS LQK decreases could indicate
widespread and uniform impairment.
Individual MOS LQK decreases indicate bursty
impairment.
Check to see if the phone is using a different
codec than expected (RxType and TxType).
Check to see if the MOS LQK version changed
after a firmware upgrade.
Network impairment from packet loss or high
jitter.
Noise or distortion in the audio channel such as
echo or audio levels.
Tandem calls that undergo multiple
encode/decode such as calls to a cellular
network or calling card network.
Acoustic problems coming from a
speakerphone, handsfree cellular phone or
wireless headset.
Where to Go for More Troubleshooting Information
Table 9-5 for general
9-19