Girls, hello! My child is sleeping under the melody + sound of rain. A…

Girls, hello! My child is sleeping under the melody + sound of rain. And all night it's this sound. Today I tried to remove it. Here again at 4 am he wakes up crying. I put the melody on and he sleeps further. Please tell me, is it harmful? He just jerks at every rustle. Even if he closes his eyes and wakes up to it. And one he doesn't sleep. He always hugs tightly.