Thank you very much for your feedback!
When I started making the game I immediately did use the same hitting sound for the player as for the teacher. Actually, teacher was made later and used the player's sound. Unfortunately, I had to remove the player's hit sound due to performance reasons.
Somehow, when the player hits space, there's a very small lag when the sound plays, depending on a device. Even if the lag was super tiny, it still affected the playing so much that I couldn't play any rhythm at all - I would slow down or just mess the rhythm. It was a difficult decision for me, because it is somewhat illogical from the reality point of view, I decided to remove the sound until I optimize the lag.
Sorry for the inconvenience. I'm very glad you liked my game, thank you!