Hey guys! Long time lurker, first time poster! Feel free to tell me if I posted this in the wrong spot. Anyways, I just took of the case I've been using on my phone for the back three months to do some spring cleaning and I found some unexpected dirt. Some was easy to clean up with a cloth, but there is this one area I can not get rid of! I'm afraid to use water because it's so close to the headphone jack, so any non-liquid solutions would be great! Here's a picture: Thanks!