The default one is Rythmbox.
You have to add the MP3 Plugin (when it starts for 1st time it says they aren't and shows a button to get them).
Besides the common features, it's not obvious how to repeat same melody.
Well, the solution I have is to search for it until remains the only one in list.
Then just Play.
It will be repeated if you have Repeat activated (CTRL+R).