I'd guess your max 50 limit was down to the car or cd player/head unit .. I had cd's with over 100 on and they played fine ... Nowadays I have a bluetooth dongle hooked up to the cd unit and play off the phone, but I haven't used cd mp3's for many years now.I had a problem years ago with a car and that wouldn't accept a disc with over 50 mp3's even though it was only half full. Just wondered before I order some blank cd's. Are they still a thing?
I don't own any Little Mix you will be glad to know
Who are Little Mix