diff --git a/include/bluetooth/audio/csis.h b/include/bluetooth/audio/csis.h
index 0691d391b02..2406fd39e31 100644
--- a/include/bluetooth/audio/csis.h
+++ b/include/bluetooth/audio/csis.h
@@ -242,14 +242,12 @@ typedef void (*bt_csis_client_lock_set_cb)(int err);
 /**
  * @brief Callback when the lock value on a set of a connected device changes.
  *
- * @param conn    Connection of the CSIS server.
  * @param set     The set that was changed.
  * @param locked  Whether the lock is locked or release.
  *
  * @return int Return 0 on success, or an errno value on error.
  */
-typedef void (*bt_csis_client_lock_changed_cb)(struct bt_conn *conn,
-					       struct bt_csis_client_set *set,
+typedef void (*bt_csis_client_lock_changed_cb)(struct bt_csis_client_set *set,
 					       bool locked);
 
 /**
diff --git a/subsys/bluetooth/audio/csis_client.c b/subsys/bluetooth/audio/csis_client.c
index 77d1bba031d..2257f12fcf6 100644
--- a/subsys/bluetooth/audio/csis_client.c
+++ b/subsys/bluetooth/audio/csis_client.c
@@ -321,7 +321,7 @@ static uint8_t lock_notify_func(struct bt_conn *conn,
 				client = &client_insts[bt_conn_index(conn)];
 				set = &client->set_member->sets[csis_inst->cli.idx];
 
-				csis_client_cbs->lock_changed(conn, set, locked);
+				csis_client_cbs->lock_changed(set, locked);
 			}
 		} else {
 			BT_DBG("Invalid length %u", length);
diff --git a/tests/bluetooth/bsim_bt/bsim_test_audio/src/csis_client_test.c b/tests/bluetooth/bsim_bt/bsim_test_audio/src/csis_client_test.c
index 732394740d3..541ed68d51f 100644
--- a/tests/bluetooth/bsim_bt/bsim_test_audio/src/csis_client_test.c
+++ b/tests/bluetooth/bsim_bt/bsim_test_audio/src/csis_client_test.c
@@ -75,8 +75,7 @@ static void csis_discover_cb(struct bt_csis_client_set_member *member, int err,
 	discovered = true;
 }
 
-static void csis_lock_changed_cb(struct bt_conn *conn,
-				 struct bt_csis_client_set *set,
+static void csis_lock_changed_cb(struct bt_csis_client_set *set,
 				 bool locked)
 {
 	printk("Set %p %s\n", set, locked ? "locked" : "released");