how can i fix my red mango angora mr118 digital audio player it is jammed?

I bought a red mango mp3 player from argos last week and it won,t work properly It has loaded all my music on, but then it plays a few songs then it jams after playing about four songs and I can,t get it to play anything else it is stuck on one song won,t go back or foward I erased all the info on it, then downloaded everything again thought it had worked but only played four songs again then jamed on one song different one from the last time but same place What can I do As ARGOS refuses to exchange it. Havent I got right.