(define clock:update-metro
   (lambda (server-process local-process)
      (clock:sync-adjust server-process local-process 5 500 .005)
      (let ((res (ipc:call server-process local-process '-clock:metro-from-host-)))
   (set! *metro* (make-metro (car res)
           (cons (clock->samples (cadr res))
           (caddr res)))))))