How many tracks are needed for good random playback

Hi all,

I am wondering how many audio files, in my case mp3 files, are needed to let the random music play work good.
At this moment I have about 320 tracks in my music folder. I have more, but these belong to my absolute favourites.

Now it always happens that with the random generated list, by Serviio, there are several tracks double or more times selected, up to three times. From the 100 presented tracks, at least 6 to 9 are double or tripple.

I know that some random players, like OTS DJ, need a lot of tracks to work correct.

So that's why I'm wondering if there is a minimum number of tracks needed for Serviio to give 100 unique tracks and no doubbles.

This is something that I'm experience since the first time, some years ago now, I started using Serviio.
Never had the time to dive into it and post my question here.

Thanks!

Hans

P.s. Sorry if someone else already posted the same question, couldn't find it with search.