Playback Function

Fast forward / backward (2x, 4x, 8x, 16x), Slow forward (1/2x, 1/4x, 1/8x, 1/16x)
Fast forward / backward (2x, 4x, 8x,16x)
Fast forward / backward (2x, 4x, 8x,16x), Slow forward (1/2x, 1/4x, 1/8x,1/16x)