static int _sample_rate_callback (nframes_t nframes, void *arg);
static int _bufsize_callback (nframes_t nframes, void *arg);
static void _jack_timebase_callback (jack_transport_state_t, nframes_t, jack_position_t*, int, void*);
static int _jack_sync_callback (jack_transport_state_t, jack_position_t*, void *arg);
static void _freewheel_callback (int , void *arg);
static void _registration_callback (jack_port_id_t, int, void *);
static int _sample_rate_callback (nframes_t nframes, void *arg);
static int _bufsize_callback (nframes_t nframes, void *arg);
static void _jack_timebase_callback (jack_transport_state_t, nframes_t, jack_position_t*, int, void*);
static int _jack_sync_callback (jack_transport_state_t, jack_position_t*, void *arg);
static void _freewheel_callback (int , void *arg);
static void _registration_callback (jack_port_id_t, int, void *);