1. Unplug the power cord of the phone, and then plug it again.
At startup, and then press and hold the MUTE button on the speaker body. (MUTE button on the body is a red circle part of the photos below.)
When the red LED is lit, I will release the MUTE button.
Red LED flashes every second, you will Factory Reset mode. (Continue to do nothing, it will time out in 20 seconds.)
2. In the condition that the above Factory Reset mode, press the MUTE button again, and then release.
Then red LED flashes twice every second, which means that you have selected the Delete setting.
(Continue to do nothing, it will time out in 20 seconds.)
3. In the above conditions, please press and hold the MUTE button for two seconds. Red LED flashes 10 times,
Setting is deleted, CP-8831 will start.