I listened for about an hour almost at a volume of 60-70%. after I stopped the video for quite a long time, with my tinnitus, I still heard these frequencies in a slightly modified form, is this normal? why is this happening?
The phantom effect of "I still hear the tone when I pause or stop the track" should fade after a minute or two. It's similar to the optical illusion of staring at a bright object for a while then looking away: the stimulus remains even when the source is removed. Keeping the volume LOW (20-40% max) will reduce this!
NIkola