Perhaps the problem with your viewpoint is that what is actually reality you view as "leftist." Things like evolution, for example-it astonishes me that people in my grandparents' days actually believed in creationism. For a sizeable amount of the GOP (including ALL their current Presidential candidates except Huntsman and perhaps Romney (at least today's belief for Romney)) to believe in creationism in the 21st century just absolutely buggers my imagination. And then they whine because others don't give their crackpot beliefs a equal time and credibility.
As for the music used being proof of NPR's leftist tendencies, I'd like a concrete example illustrating that alleged bias. For example, using Darth Vader's theme as the lead-in to an interview with Cheney-never heard NPR do that. Mostly their music is like 10,000 variations of their theme song. For very sad occassions (like when 9/11 occured and its immediate aftermath) they use very somber, funeral like dirges.