If your Theremini continues to drone when it is not being played, you may want to use the Auto Mute feature. Auto Mute will cause the Theremini to stop making sound when you are physically away from your Theremini’s Pitch antenna. To activate Auto Mute, press the SETUP button to enter the Setup menu and keep pressing SETUP until you reach the Auto Mute page.

If you do not want to use auto mute, you can simply drape the Theremini’s power or audio cable over the volume antenna when not in use.