Dr. Dre will be gearing for more competition from rappers who are getting into the headphones business, the most recent being 50 Cent. Fifty, also known as Curtis Jackson, has his own headphones company SMS Audio , which recently acquired KonoAudio for an undisclosed amount. SMS Audio is set to unveil a line-up of new products in the coming weeks. That is, if the plan pushes through. You see, it already happened before, when 50 Cent inked a deal with Sleek Audio to produce and distribute a wireless hybrid headphone system called Sleek by 50. Protoypes were even showed off at CES 2011, but the deal fell apart last May. SMS Audio, part of 50’s G-Unit Brands, then picked up where it left off and plans on releasing at least three headphones. The company has yet to announce anything about its upcoming headphones, but it revealed that the line will consist of three categories: Wired, wireless, and earbuds. There are also reports that one of its products will feature a...