diff --git a/libs/ardour/async_midi_port.cc b/libs/ardour/async_midi_port.cc
index 8c227c50dc..0b38f0966c 100644
--- a/libs/ardour/async_midi_port.cc
+++ b/libs/ardour/async_midi_port.cc
@@ -29,6 +29,8 @@
 
 #include "midi++/types.h"
 
+#include "temporal/tempo.h"
+
 #include "ardour/async_midi_port.h"
 #include "ardour/audioengine.h"
 #include "ardour/midi_buffer.h"
@@ -330,6 +332,10 @@ AsyncMIDIPort::read (MIDI::byte *, size_t)
 	uint32_t size;
 	vector<MIDI::byte> buffer(input_fifo.capacity());
 
+	if (!is_process_thread()) {
+		(void) Temporal::TempoMap::fetch();
+	}
+
 	while (input_fifo.read (&time, &type, &size, &buffer[0])) {
 		_parser->set_timestamp (time);
 		for (uint32_t i = 0; i < size; ++i) {