diff --git a/rtmp/rtmp.go b/rtmp/rtmp.go
index 47361e51..dd845783 100644
--- a/rtmp/rtmp.go
+++ b/rtmp/rtmp.go
@@ -2230,9 +2230,9 @@ func memcmp(a, b unsafe.Pointer, size int) int {
 	return 0
 }
 
-func memset(ptr *byte, val int, num int) {
+func memset(ptr *byte, val byte, num int) {
 	for i := 0; i < num; i++ {
-		(*[_Gi]byte)(unsafe.Pointer(ptr))[i] = byte(val)
+		(*[_Gi]byte)(unsafe.Pointer(ptr))[i] = val
 	}
 }
 
@@ -2343,7 +2343,7 @@ func malloc(nOfBytes uintptr) unsafe.Pointer {
 
 func calloc(val byte, noOfBytes uintptr) unsafe.Pointer {
 	mem := malloc(noOfBytes)
-	memset((*byte)(mem), int(val), int(noOfBytes))
+	memset((*byte)(mem), val, int(noOfBytes))
 	return mem
 }