To improve the microphone's ability to pick up voices on your PowerConf C200, please try the following steps:

1. Keep within 3 meters of the webcam to ensure peak performance.

2. keep your PowerConf C200's firmware up to date.

3. PowerConf C200 supports directional pickup, so you can select the angle of the device microphone pickup to reduce background noise outside that range and ensure better vocals. 

If you have additional questions, please contact us for further assistance.