You should take it to Best Buy.
I have a Windows 8 Acer Aspire laptop that suddenly has started having sound card problems. When I restart it, sound usually resumes, but then it will go again! I've done all the troubleshooting stuff. Does anyone have any ideas?
First off, Acer isn't the greatest brand for reliablity. As I used to be a Tech for a company in Cal. , my best suggestion is to take it to a Tech and have it checked. Laptops are harder to work on the desktops. It sounds like when it gets warm, a connection or circuit shuts down. Depending on it's age, that would be the best thing to do. Next time, look at ASUS brand. Great units !