Have you tried updating the drivers? Both the Sound and Video ones.
Also, it could be that the laptop may not be able to handle the 'strain' of running Windows 10. Depending on the components.
And, be sure to keep an eye on the laptops temps. There are quite a few programs you can get and install (Speedfan is a good one) to monitor the temps. High temps could be leading to your sound issues and more.