Using the Amplification Reset Override Switch (located on the back of the base)
The ClearSounds® A1600 is designed with unique features to protect users from being exposed to dangerous sound levels. You are able to switch between automatic or manual amplification, and you should select the setting that best suits your needs.
Set ON – When the Amplification Reset Override Switch 
is set to ON, the amplify function will be ON every time a call starts. The user will no longer need to remember to press the Amplify key with every telephone conversation. When the phone hangs up, the amplify setting will remain ON.
Set OFF – When the Amplification Reset Override Switch 
is set to OFF, the amplify function will be OFF every time a call starts. This allows people who do not require the level of amplification offered on the phone to use it. Every time a call starts, the user will need to press the Amplify key in order to gain the extra level of amplification and tone control. When the phone hangs up, the Amplify key will reset to OFF.
Important: You may manually turn ON and OFF the amplify function during a conversation by simply pressing the Amplify key.
NOTE: Your ClearSounds® A1600 comes from the factory preset in the OFF position. If you would like to override the factory preset, simply change the selection on the underside of the phone to ON.