Update tests

Change-Id: I268210281a27cbef6928e4195a723736e61f1b33
diff --git a/matrix.go b/matrix.go
index 021c191..7141e74 100644
--- a/matrix.go
+++ b/matrix.go
@@ -521,6 +521,7 @@
 			}
 
 			// TODO: Better as a ring buffer
+			// buffer = buffer[buffc:]
 			for x, i := range buffer[buffc:buffi] {
 				buffer[x] = i
 			}