HP ENVY TE02-0000na video sometimes slows right down and freezes

[m6mal]

Hi i bought my PC from HP shop. it has froze completely 2 or 3 times. I was watching a video via media player and it slowed right down to slow motion and froze. i tried pressing power button and i just see the hour glass on mouse move and never shut down so i had to do a hard reset pressing button for a few seconds. I even had it freeze when it got to the end of installing nvidea updated drivers, i pressed the close button and nothing happened and the pc rebooted. I then decided to do a reset and re installed the system using local files and keep my files option. It did it fine and it even seems a bit quicker but this morning i was watching a video (ON MEDIA PLAYER NOT IN A BROWSER) and thought all was good until after continuing watching videos the sound went and the video slowed right down to a few frames per second and usually i cant get out of this and it freezes completely and i have to press the button, but today i managed to press escape and the video minimised playing slow still on the desktop so i exited the video. I was able to function as normal. I did try other players like vlc and kmplayer and same freezing. I even had it freeze once in opera browser so i uninstalled it. Anyway all i have done is reset OS yesterday and have not added drivers as it said all was good.and still it happens as i said earlier. I have run hp diagnostics a week ago and nothing came up as bad...