diff --git a/audio/interface.go b/audio/interface.go
index adbc6a3..395548c 100644
--- a/audio/interface.go
+++ b/audio/interface.go
@@ -4,7 +4,7 @@ package audio
 //
 // This value should be set at most once before using audio package. It is safe to assume that this
 // value does not change during runtime.
-var SampleRate = 48000
+var SampleRate float64 = 48000
 
 // Streamer is able to stream a finite or infinite sequence of audio samples.
 type Streamer interface {