Hi there mate! Actually I might have a solution for you if you're still having trouble fixing the issue. So basically what I've done is pretty much downloading the newest audio REALTEK drivers for Lenovo y50-70. After downloading it you just execute it and a foulder should appear in the C: disk called "drivers" and there should be a folder called "Audio Drivers" and then you just install the Realtek drivers after all the uninstalling and installing you go to the same folder again and there is a folder called "DS1" there you will find two installers "Dolby Digital Plus HT" that was the one I needed cause it's the Dolby Digital Plus Home Theater and the other one is "Dolby Digital Plus AA" didn't use it, but I think it's the Advanced Audio one. So yeah tell me if it worked or not. Mine doesn't appear on startup, so I have to turn it manually, but yeah atleast it works fine Cheers!
@ThirdPerson Thank you for your help! Actually, I only needed to reinstall the Dolby application because my audio drivers were already the latest version.
PS: Before, when this application was working, I also had to manually turn it on during startup.