diff --git a/utilities/shuffle.sh b/utilities/shuffle.sh
index 5da1fc3..ccff049 100755
--- a/utilities/shuffle.sh
+++ b/utilities/shuffle.sh
@@ -9,6 +9,9 @@ mkdir shuffled;
 
 for file in $to_shuffle; do
 	rand=$RANDOM
+	while test -f "shuffled/$rand.${extension}"; do
+		rand=$RANDOM
+	done
 	mv ${file} shuffled/$rand.${extension}
 done