diff --git a/gr-uhd/lib/gr_uhd_usrp_sink.cc b/gr-uhd/lib/gr_uhd_usrp_sink.cc
index 6216c94..475440c 100644
--- a/gr-uhd/lib/gr_uhd_usrp_sink.cc
+++ b/gr-uhd/lib/gr_uhd_usrp_sink.cc
@@ -407,6 +407,7 @@ public:
     bool start(void){
         #ifdef GR_UHD_USE_STREAM_API
         _tx_stream = _dev->get_tx_stream(_stream_args);
+        this->set_output_multiple(_tx_stream->get_max_num_samps());
         #endif

         _metadata.start_of_burst = true;