Windows 10 was released in a BETA like state, it really wasn't as polished as previous boxed releases because with the world the way it is now (internet updates) there is the release now, patch later mentality.
Lots of people reported having audio and wifi driver issues after moving to 10, MS hasn't really made sure driver manufacturers were ready for the release. I went back to 8.1 only after half an hour on my Surface, couldn't stand 10! Hopefully it will get better over the next few months.