diff --git a/application/src/Api/Adapter/MediaAdapter.php b/application/src/Api/Adapter/MediaAdapter.php
index 777a3fd578..3c33f1bdb0 100644
--- a/application/src/Api/Adapter/MediaAdapter.php
+++ b/application/src/Api/Adapter/MediaAdapter.php
@@ -48,7 +48,7 @@ public function buildQuery(QueryBuilder $qb, array $query)
             ));
         }
 
-        if (isset($query['media_type'])) {
+        if (!empty($query['media_type'])) {
             $qb->andWhere($qb->expr()->eq(
                 'omeka_root.mediaType',
                 $this->createNamedParameter($qb, $query['media_type'])