I have the same model number purchased in Feb of 2014 which stopped cooling in the fridge compartment as well. We bought a small thermometer and noticed the fridge was not cooling below 55ºF. Originally called Samsung and they setup an appointment with their service technician but the tech was going to charge us $200 just for the visit. I wasn't sure if it was a sealed system so we had another more affordable technician come out. He was a former Samsung tech. He came in, told me the issue was the fridge compressor and didn't even charge me out of good conscience because he said it was unrepairable due to the fact it uses flammable R600a. I am now going to have to go through the Samsung process to get the tech out here to basically tell Samsung the same thing I already know.
I've already had to purchase a new fridge (never model of the same fridge) because we've been without one for over a month. The former Samsung tech told me that the newer Samsung fridges no longer use R600a because of this issue.