Adjusting the Handset Rest
Set the handset aside and pull the square plastic tab from the handset rest.
Rotate the tab halfway (180 degrees).
Hold the tab between two fingers, with the small notches (in the corners) facing you.
Make sure the tab lines up evenly with the slot in the cradle.
Slide the tab back into the handset rest. An extension protrudes from the top of the rotated tab. Return the
handset to the handset rest.
Cisco Unified IP Phone 3905 User Guide for Cisco Unified Communications Manager Express Version 8.8 (SIP)