I have recently checked my MOTU interface with another DAW which is "Reaper", and surprisingly by setting the higher sample rates on it didn't disturb my sound, where as before I was indeed using an unlicensed DAW which exactly caused this problem (all thanks to Matt!), so all the efforts were not in vain, and I'm happy that everything is fine with MOTU yeah and I wanna huge thanks to rharv for those very valuable reasons for using lower sample rate cause I'm not new to music, but those things I really should've known in the first place so will keep that in my mind!..
In other words an issue have been solved!

Cheers!

OK