diff --git a/src/Model/Item.php b/src/Model/Item.php
index 7bc8270a17..2b57557ca8 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -2885,7 +2885,7 @@ class Item
 						'mime'   => $attachment['mimetype'],
 					],
 				]);
-				if ($item['post-type'] == Item::PT_AUDIO) {
+				if (($item['post-type'] ?? null) == Item::PT_AUDIO) {
 					$leading .= $media;
 				} else {
 					$trailing .= $media;