diff --git a/libs/backends/alsa/alsa_audiobackend.cc b/libs/backends/alsa/alsa_audiobackend.cc
index 5c267d6c7f..0d7e33cd63 100644
--- a/libs/backends/alsa/alsa_audiobackend.cc
+++ b/libs/backends/alsa/alsa_audiobackend.cc
@@ -2319,7 +2319,7 @@ void* AlsaMidiPort::get_buffer (pframes_t /* nframes */)
 				(_buffer[_bufperiod]).push_back (boost::shared_ptr<AlsaMidiEvent>(new AlsaMidiEvent (**it)));
 			}
 		}
-		std::sort ((_buffer[_bufperiod]).begin (), (_buffer[_bufperiod]).end (), MidiEventSorter());
+		std::stable_sort ((_buffer[_bufperiod]).begin (), (_buffer[_bufperiod]).end (), MidiEventSorter());
 	}
 	return &(_buffer[_bufperiod]);
 }
diff --git a/libs/backends/coreaudio/coreaudio_backend.cc b/libs/backends/coreaudio/coreaudio_backend.cc
index 504a7376f9..0ef1e6332b 100644
--- a/libs/backends/coreaudio/coreaudio_backend.cc
+++ b/libs/backends/coreaudio/coreaudio_backend.cc
@@ -2142,7 +2142,7 @@ void* CoreMidiPort::get_buffer (pframes_t /* nframes */)
 				(_buffer[_bufperiod]).push_back (boost::shared_ptr<CoreMidiEvent>(new CoreMidiEvent (**it)));
 			}
 		}
-		std::sort ((_buffer[_bufperiod]).begin (), (_buffer[_bufperiod]).end (), MidiEventSorter());
+		std::stable_sort ((_buffer[_bufperiod]).begin (), (_buffer[_bufperiod]).end (), MidiEventSorter());
 	}
 
 	return &(_buffer[_bufperiod]);
diff --git a/libs/backends/dummy/dummy_audiobackend.cc b/libs/backends/dummy/dummy_audiobackend.cc
index 28d73d462e..73ddc8225b 100644
--- a/libs/backends/dummy/dummy_audiobackend.cc
+++ b/libs/backends/dummy/dummy_audiobackend.cc
@@ -2134,7 +2134,7 @@ void* DummyMidiPort::get_buffer (pframes_t n_samples)
 				_buffer.push_back (boost::shared_ptr<DummyMidiEvent>(new DummyMidiEvent (**it)));
 			}
 		}
-		std::sort (_buffer.begin (), _buffer.end (), MidiEventSorter());
+		std::stable_sort (_buffer.begin (), _buffer.end (), MidiEventSorter());
 	} else if (is_output () && is_physical () && is_terminal()) {
 		if (!_gen_cycle) {
 			midi_generate(n_samples);
diff --git a/libs/backends/portaudio/portaudio_backend.cc b/libs/backends/portaudio/portaudio_backend.cc
index b25a54f7a9..c2402a994d 100644
--- a/libs/backends/portaudio/portaudio_backend.cc
+++ b/libs/backends/portaudio/portaudio_backend.cc
@@ -2374,7 +2374,7 @@ void* PortMidiPort::get_buffer (pframes_t /* nframes */)
 				(_buffer[_bufperiod]).push_back (boost::shared_ptr<PortMidiEvent>(new PortMidiEvent (**it)));
 			}
 		}
-		std::sort ((_buffer[_bufperiod]).begin (), (_buffer[_bufperiod]).end (), MidiEventSorter());
+		std::stable_sort ((_buffer[_bufperiod]).begin (), (_buffer[_bufperiod]).end (), MidiEventSorter());
 	}
 	return &(_buffer[_bufperiod]);
 }