Voice Quality Troubleshooting Tips; Cisco Ip Phone Cleaning - Cisco 7821 Administration Manual

Cisco IP Phone Cleaning

You can access voice quality metrics from the Cisco IP Phone using the Call Statistics screen or remotely by
using Streaming Statistics.

Voice Quality Troubleshooting Tips

When you observe significant and persistent changes to metrics, use the following table for general
troubleshooting information.
Table 29: Changes to Voice Quality Metrics
Metric change
Conceal Ratio and Conceal Seconds
increase significantly
Conceal Ratio is near or at zero, but
the voice quality is poor.
Voice quality metrics do not account for noise or distortion, only frame loss.
Note
Cisco IP Phone Cleaning
To clean your Cisco IP Phone, use only a dry soft cloth to gently wipe the phone and the phone screen. Do
not apply liquids or powders directly to the phone. As with all non-weatherproof electronics, liquids and
powders can damage the components and cause failures.
When the phone is in sleep mode, the screen is blank and the Select button is not lit. When the phone is in
this condition, you can clean the screen, as long as you know that the phone will remain asleep until after you
finish cleaning.
Cisco IP Phone 7821, 7841, and 7861 Administration Guide for Cisco Unified Communications Manager 10.0
(SIP)
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Condition
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.
Check packet transmit (TxCnt) and packet receive (RxCnt) counters
to verify that voice packets are flowing.