diff --git a/multiplex_test.go b/multiplex_test.go
index e594d0f..4d0df2a 100644
--- a/multiplex_test.go
+++ b/multiplex_test.go
@@ -2,9 +2,9 @@ package multiplex
 
 import (
 	"context"
+	"crypto/rand"
 	"fmt"
 	"io"
-	"math/rand"
 	"net"
 	"os"
 	"sync"