Cisco Systems 8.6 manual Where to Go for More Troubleshooting Information, Troubleshooting Tips

Chapter 9 Troubleshooting and Maintenance

Where to Go for More Troubleshooting Information

Troubleshooting Tips

When you observe significant and persistent changes to metrics, use Table 9-5for general troubleshooting information:

Table 9-5 Changes to Voice Quality Metrics

Metric Change	Condition
MOS LQK scores decrease	Network impairment from packet loss or high jitter:
significantly	• Average MOS LQK decreases could indicate widespread
	and uniform impairment.
	• Individual MOS LQK decreases indicate bursty
	impairment.
	Cross-check with Conceal Ratio and Conceal Seconds for
	evidence of packet loss and jitter.
MOS LQK scores decrease	• Check to see if the phone is using a different codec than
significantly	expected (RxType and TxType).
	• Check to see if the MOS LQK version changed after a
	firmware upgrade.
Conceal Ratio and Conceal	• Network impairment from packet loss or high jitter.
Seconds increase significantly
Conceal Ratio is near or at zero,	• Noise or distortion in the audio channel such as echo or
but the voice quality is poor.	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.
	Check packet transmit (TxCnt) and packet receive (RxCnt)
	counters to verify that voice packets are flowing.

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.

•Cisco Unified IP Phone Troubleshooting Resources:

http://www.cisco.com/en/US/products/hw/phones/ps379/tsd_products_ support_series_home.html

•Cisco Products and Services (Technical Support and Documentation):

http://www.cisco.com/en/US/products/sw/voicesw/tsd_products_support_ category_home.html

	Cisco Unified IP Phone Administration Guide for Cisco Unified Communications Manager 8.6 (SCCP and SIP)
OL-23091-01		9-17