diff --git a/src/libsysprof-profile/sysprof-perf-event-stream.c b/src/libsysprof-profile/sysprof-perf-event-stream.c
index 17a36643..dc9bf0c0 100644
--- a/src/libsysprof-profile/sysprof-perf-event-stream.c
+++ b/src/libsysprof-profile/sysprof-perf-event-stream.c
@@ -366,15 +366,15 @@ sysprof_perf_event_stream_new (GDBusConnection          *connection,
 
   g_dbus_connection_call_with_unix_fd_list (connection,
                                             "org.gnome.Sysprof3",
-                                            "/org/gnome/Sysprof3/Service",
+                                            "/org/gnome/Sysprof3",
                                             "org.gnome.Sysprof3.Service",
                                             "PerfEventOpen",
-                                            g_variant_new ("(@a{sv}ii@ht)",
+                                            g_variant_new ("(@a{sv}iiht)",
                                                            g_variant_dict_end (&options),
                                                            -1,
                                                            cpu,
                                                            group_fd_handle,
-                                                           flags),
+                                                           (guint64)flags),
                                             G_VARIANT_TYPE ("(h)"),
                                             G_DBUS_CALL_FLAGS_NONE,
                                             G_MAXUINT,