title: strange Math.sin behaviour
body: <p>I'm making a program that plays a sine wave varying in pitch and I'm dealing with something that i've never seen before: the program should play a sine wave from 220 hz to 0 hz, and I can see the frequency going from 220 to 0, but what I hear is a sine wave that goes from 220 to 0 and then back to 220.
  I have no idea how this piece of code can do that</p>
  
  <p><a href="http://pastebin.com/HS36k7XJ" rel="nofollow">http://pastebin.com/HS36k7XJ</a> (had to post it here because of screwed up layout)</p>
  
  <p>(where t is the time in seconds and f the current frequency (which is calculated by a simple linear interpolation, which behaves properly))</p>