Hello FabianS,
Thank you for getting back to us.
What do you mean by "Whenever I try to talk the sound is very quiet"?
Are you able to hear your PC sound from your recorded video normally?
If not, please refer to the following page and increase the output volume of the default sound device and the recording target. (Step 2-2)
https://www.bandicam.com/faqs/no_sound_ ... x_problem/
Do I need to buy a mic for the sound to work good?
Yes, if you'd like to record your voice with PC screen, game screen and the PC sound, you need to connect a microphone to your PC.
After connecting a microphone, please refer to the following link.
* How to record your voice in Windows Vista/7/8/10
https://www.bandicam.com/faqs/how_to_re ... icrophone/
Thank you.