Issue about importing master files into Cubase Project and the sound distorts a bit!

So, I set the project detail the exact, 48-24 and then
imported all WAV files to different tracks.

But strangily the low end part disorts slightly but, it does not when I just listen through Mac preview option…

Will I be having wrong setting inside within my Cubase Pro 11?

My masters are 48 24 wav

I normally work at 48-32(float) but since the mastering engineer sent me in this format, I’ve just switched from 32float point to 24.

Why would my masters distort a bit inside Cubase project but not distort outside (mac preview space bar playback tool)…?

Very strange huh…?