Maintenance
Basic Reset
Performing a basic reset of a Cisco IP Phone provides a way to recover if the phone experiences an error and provides a way to reset or restore various configuration and security settings.
The following table describes the ways to perform a basic reset. You can reset a phone after the phone has started up. Choose the operation that is appropriate for your situation.
Operation |
Action |
Explanation |
---|---|---|
Restart phone |
Press Services, Applications, or Directories and then press **#**. |
Resets any user and network setup changes that you have made, but that the phone has not written to its Flash memory, to previously saved settings, then restarts the phone. |
Reset the Phone to the Factory Settings from the Keypad
You can reset the phone to the factory settings. The reset clears all the phone parameters.
Command or Action | Purpose |
---|
Perform Factory Reset from Phone Menu
Voice Quality Monitoring
To measure the voice quality of calls that are sent and received within the network, Cisco IP Phones use these statistical metrics that are based on concealment events. The DSP plays concealment frames to mask frame loss in the voice packet stream.
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Concealment Ratio metrics: Show the ratio of concealment frames over total speech frames. An interval conceal ratio is calculated every 3 seconds.
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Concealed Second metrics: Show the number of seconds in which the DSP plays concealment frames due to lost frames. A severely "concealed second" is a second in which the DSP plays more than five percent concealment frames.
Note | Concealment ratio and concealment seconds are primary measurements based on frame loss. A Conceal Ratio of zero indicates that the IP network is delivering frames and packets on time with no loss. |
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.
Note | Voice quality metrics do not account for noise or distortion, only frame loss. |
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.