Same Song"s" keep repeating in my iTunes playlist

Hi Support Team, I have have a iPhone 7 and have a number of playlists in my iTunes app. I sync these lists from iTunes on my MacBook Pro 2012 edition. My biggest playlist has 906 songs in it.

My music is NOT ON REPEAT.

When I shuffle the list and play, it is always the same group of songs that come up first in the shuffle. And if I check the number of plays of songs in the list - there are songs that have not even been played! If you take my meaning :)

So after much searching and enquiring online - nothing - only advice on how to turn the repeat song / list shuffle. I don't think that is the problem.

I think there is something in the logic or how the shuffle thing is working - why does the same songs always come up in the first 20 / 50 songs played?

Can you check and help?

Are there any other iTunes users having the same issue?