This is a fairly easy achievement in order to unlock.
In game while roaming about, preferably, be in a safe location away from any zombies, select down on the d-pad (
) to load the inventory tab up and click LB twice (
) to open up the radio tab. For me, this gives me 8 different options including 2 sub menus - I have the Ultimate Edition so I will have a few more options for the DLC packs. As far as I am aware, any option you select in this menu will unlock the achievement, without any DLC content, I would attempt to select the 'Locate Plague Heart' option for 350 Influence - This should be a definite unlock for the achievement.