Napy, I have read back thru this thread and the other posted by you and I must tell you that old LC have a headache. Fortunate for you I have medication for that.
Now if you would be kind enough to clarify some things for me.
1st. The sound issue didn't start until you upgraded to Windows 10. Is this correct?
2nd. The sound issue only happens when the volume is above 50%?
3rd. Your laptop has the IDT High-Definition (HD) Audio and you have the Beats Audio controller software installed?
If you have answered yes to all three then go to
HP Customer Support , download and install the drivers called
High-Definition (HD) Audio Driver. These are audio drivers to fix known audio issues.