diff --git a/src/library/coverartcache.cpp b/src/library/coverartcache.cpp
index e86e69150824..fa4507e65390 100644
--- a/src/library/coverartcache.cpp
+++ b/src/library/coverartcache.cpp
@@ -15,7 +15,7 @@ mixxx::Logger kLogger("CoverArtCache");
 
 QString pixmapCacheKey(quint16 hash, int width) {
     return QString("CoverArtCache_%1_%2")
-            .arg(QString::number(hash)).arg(width);
+            .arg(QString::number(hash), QString::number(width));
 }
 
 // The transformation mode when scaling images