player: Use floating point arithmetic instead of AVRational
player: Use floating point arithmetic instead of AVRational

av_mul_q calls av_reduce, whose runtime depends on its inputs. This is
a latency-sensitive calculation though.

gnowxilef/pianobar,gnowxilef/pianobar,gnowxilef/pianobar,gnowxilef/pianobar,gnowxilef/pianobar,gnowxilef/pianobar