diff --git a/src/pipewire-jack.c b/src/pipewire-jack.c
index 1b6cfda79..27fcf9cfc 100644
--- a/src/pipewire-jack.c
+++ b/src/pipewire-jack.c
@@ -858,7 +858,7 @@ static int client_node_set_io(void *object,
 	uint32_t tag[5] = { c->node_id, id, };
 
         if (mem_id == SPA_ID_INVALID) {
-		if ((mm = pw_mempool_find_tag(c->remote->pool, tag)) != NULL)
+		if ((mm = pw_mempool_find_tag(c->remote->pool, tag, sizeof(tag))) != NULL)
 			pw_memmap_free(mm);
 		mm = ptr = NULL;
 		size = 0;
@@ -1300,7 +1300,7 @@ static int client_node_port_set_io(void *object,
 	}
 
         if (mem_id == SPA_ID_INVALID) {
-		if ((mm = pw_mempool_find_tag(c->remote->pool, tag)) != NULL)
+		if ((mm = pw_mempool_find_tag(c->remote->pool, tag, sizeof(tag))) != NULL)
 			pw_memmap_free(mm);
 
                 mm = ptr = NULL;