Regarding how to reset a PowerConf speakerphone, please see the chart below:

 

Product Name

Reset

PowerConf

PowerConf+

PowerConf S3

1. press and hold down the Bluetooth button 

2. press the Volume "-" button until the square indicator flashes four times

PowerConf S500

1. press and hold down the Bluetooth button 

2. press volume "-" button until the light bar turns red, after that, the speakerphone will restart

PowerConf S330

N/A