Speaker and camera of my MacBook Air aren't working after installing windows
Have you tried re-installing the drivers?

From Apple official page:
https://support.apple.com/kb/DL1836?viewlocale=en_US&amp;locale=en_US

Facetime drivers:
https://support.apple.com/kb/DL1831?viewlocale=en_US&amp;locale=en_US

Hope this helps.

Cheers.