fix beats

src/main.rs

@@ -28,8 +28,8 @@ fn play(mut s: seq::SynSeq, sample_rate: usize, bpm: usize) {
         sample_rate: sample_rate,
         channel_sample_count: samples_per_beat,
     };
-    let beats = s.beats();
-    let duration = 1 + 60 * beats / bpm;
+    let beats = s.beats() + 3;
+    let duration = 60 * beats / bpm;
 
     let sample_count = (params.channel_sample_count) as usize;
     let mut left: Vec<f32> = vec![0_f32; sample_count];