diff --git a/src/examples/media-session/policy-node.c b/src/examples/media-session/policy-node.c
index 876ecdb77..16216c4ba 100644
--- a/src/examples/media-session/policy-node.c
+++ b/src/examples/media-session/policy-node.c
@@ -844,7 +844,8 @@ static int metadata_property(void *object, uint32_t subject,
 
 			if (dst_node && src_node)
 				handle_move(impl, src_node, dst_node);
-		} else if (val == SPA_ID_INVALID && strcmp(key, "target.node") == 0) {
+		} else if (val == SPA_ID_INVALID && key != NULL &&
+				strcmp(key, "target.node") == 0) {
 			/* Unset target node. Schedule rescan to re-link, if needed. */
 			struct node *src_node;
 			src_node = find_node_by_id(impl, subject);