Hello all, I've been an avid reader of head-fi for a while but this is my first post. So the headphone port on my desktop broke and the headphone out port on my speakers introduces all sorts of hissing. I am looking for a portable USB DAC/headphone amp that I could use with my desktop or laptop to drive a pair of Sennheiser HD555's or Shure SE215-k's with better quality than the integrated sound and without the horrible hiss coming from my speakers. I like the look of the iBasso D-Zero since its gotten slightly better reviews than the Fiio E7 and the iBasso fits pretty well into my price range as I'm a college student who can't afford to throw down tons of cash on sweet sound equipment. This is my first foray into USB DAC territory so I'm not sure if this is the best choice. Would the iBasso be the best bang for my buck for an entry level audio enthusiast or is there something better? I'd really like to not spend more than $120 on this but I could suffer up to $150 if the deal was super sweet. I appreciate your input!!