By default, the DW/SD/D10 headsets will produce a beep in the speaker when muted to remind the user that mute is enabled.
To disable the mute notification on your DW/SD/D10 headset, you must have EPOS Connect installed.
Once installed open EPOS connect and click settings.
Once in settings click DECT turn the Mute tone to OFF and click save in the bottom right corner. 