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APU-7/APU-70/APU-71 (EHS Cable): How to Install on a Cisco Phone

This procedure explains how to install the APU-7/APU-70/APU-71 EHS cable, which is compatible with the following Cisco phone models:

  • 8961
  • 9951
  • 9971


Software Requirements

  • The Cisco server must be running Cisco CallManager System Version 4.1(3)SR5x or higher. Check with your telephone administrator to verify this.
  • The Cisco phone must be running firmware 8.3(3)x or higher. To find your firmware version, press the Settings button on the phone (the checkbox icon). Select "Model information." The firmware revision is listed under "Load File."

Phone Settings

The phone must have

  • "Headset Enabled" = Yes
  • "Headset Hookswitch Control" = Enabled.

To verify this:

  1. Press the Settings button on the phone (the checkbox icon). Select "Device Configuration" > "Media Configuration."
  2. If "Headset Enabled" is "No" and/or "Headset Hookswitch Control" is "Disabled," contact your telephone administrator.

To Install the EHS Cable

  1. On your base, set your compatibility switch and speaking and listening volumes to the following:
    SettingCS50/CS55/CS70/CS70N/ CS351N/CS361N
    Cable APU-7
    CS500 Series
    Cable APU-70 or APU-71
    Savi Office/700 Series
    Cable APU-70 or APU-71
    Speaking VolumeB44
    Listening Volume244
     Image of SettingsImage of SettingsImage of Settings
  2. Connect your EHS cable to your phone as follows: