iTunes songs randomly trim themselves

Hello, some of my iTunes songs have been trimming themselves at the beginning and at the end. It's starting to be annoying, may I please have some help for that?

iPhone 7

iOS 10.2

I have tried other songs to see if that happens to other songs, but it was just a few songs and they went back to normal after that. That has happened to me several times in within 3-4 months.