At the start of chapter 15 - Hunting Season you will have to talk to Baron regarding the infiltrator and tracking a messenger. On your way out, Ryan will talk to you and will give you a side quest to find a boombox for his tape. Leave the bunker
In the next area, head to the blue diamond on your map that's marked 'Radio For Ryan". When you get into the building, head upstairs and take out the 2 terminators waiting for you and grab the boombox of the table. Now just continue on with the main mission
Once you get back to the resistance base, exit the room your in and turn right. The first room on your left will have Ryan and his newly acquired boom box. Turn it on, then hold X to turn up the volume.
Alvin will curse and you will get the achievement