Hi @Basam,
The Dynamic Vibration System has individual level settings for each application. You can have it turned off in Spotify, but turned on, on a certain level, on Playstation Video for example.
To activate Dynamic Vibration system just press volume up or down while playing something that also has sound and there should be two level control bars at the top of your screen. The first one is the sound volume, and the second one is the vibration level.
