diff --git a/libs/ardour/test/data/mantis_3356/mantis_3356.ardour b/libs/ardour/test/data/mantis_3356/mantis_3356.ardour
index 5a0927ae33..5a3f5271c8 100644
--- a/libs/ardour/test/data/mantis_3356/mantis_3356.ardour
+++ b/libs/ardour/test/data/mantis_3356/mantis_3356.ardour
@@ -46,7 +46,7 @@
   </Locations>
   <Bundles/>
   <Routes>
-    <Route id="19" name="master" default-type="audio" flags="MasterOut" active="yes" phase-invert="no" denormal-protection="no" meter-point="MeterPostFader" order-keys="editor=0:signal=0" self-solo="no" soloed-by-upstream="0" soloed-by-downstream="0">
+    <Route id="19" name="master" default-type="audio" flags="MasterOut" active="yes" phase-invert="0" denormal-protection="no" meter-point="MeterPostFader" order-keys="editor=0:signal=0" self-solo="no" soloed-by-upstream="0" soloed-by-downstream="0">
       <IO name="master" id="25" direction="Input" default-type="audio">
         <Port type="audio" name="master/audio_in 1"/>
         <Port type="audio" name="master/audio_in 2"/>
@@ -84,7 +84,7 @@
         </GUI>
       </Extra>
     </Route>
-    <Route id="69" name="Midi 1" default-type="midi" active="yes" phase-invert="no" denormal-protection="no" meter-point="MeterPostFader" order-keys="editor=1:signal=1" self-solo="no" soloed-by-upstream="0" soloed-by-downstream="0" step-editing="no" note-mode="Sustained" midi-thru="yes" default-channel="0">
+    <Route id="69" name="Midi 1" default-type="midi" active="yes" phase-invert="0" denormal-protection="no" meter-point="MeterPostFader" order-keys="editor=1:signal=1" self-solo="no" soloed-by-upstream="0" soloed-by-downstream="0" step-editing="no" note-mode="Sustained" midi-thru="yes" default-channel="0">
       <IO name="Midi 1" id="76" direction="Input" default-type="midi">
         <Port type="midi" name="Midi 1/midi_in 1">
           <Connection other="alsa_pcm:SB-Live--5-1--SB0060-/midi_capture_1"/>
diff --git a/libs/ardour/test/midi_clock_slave_test.cpp b/libs/ardour/test/midi_clock_slave_test.cpp
index f953ae7851..dcb159cb2c 100644
--- a/libs/ardour/test/midi_clock_slave_test.cpp
+++ b/libs/ardour/test/midi_clock_slave_test.cpp
@@ -10,26 +10,26 @@ void
 MIDIClock_SlaveTest::testStepResponse ()
 {
   double      speed    = 1.0;
-  nframes64_t position = 0;
+  framepos_t position = 0;
 
   MIDI::Parser* parser = 0;
 
   TestSlaveSessionProxy *sess = (TestSlaveSessionProxy *) session;
-  nframes64_t period_size = 4096;
+  framecnt_t period_size = 4096;
   sess->set_period_size (period_size);
 
   bandwidth = 1.0 / 60.0;
 
-  nframes64_t start_time = 1000000;
+  framepos_t start_time = 1000000;
   start (*parser, start_time);
 
   update_midi_clock (*parser, start_time);
  
-  for (nframes64_t i = 1; i<= 100 * period_size; i++) {
+  for (framecnt_t i = 1; i<= 100 * period_size; i++) {
     // simulate jitter
-    nframes64_t input_delta = nframes64_t(one_ppqn_in_frames + 0.1 * (double(random()) / double (RAND_MAX)) * one_ppqn_in_frames);
+    framecnt_t input_delta = framecnt_t (one_ppqn_in_frames + 0.1 * (double(random()) / double (RAND_MAX)) * one_ppqn_in_frames);
     
-    if (i % nframes64_t(input_delta) == 0) {
+    if (i % input_delta == 0) {
       update_midi_clock (*parser, start_time + i);
     }
 
diff --git a/libs/ardour/test/midi_clock_slave_test.h b/libs/ardour/test/midi_clock_slave_test.h
index 5a6a6fdb4f..3b9278b872 100644
--- a/libs/ardour/test/midi_clock_slave_test.h
+++ b/libs/ardour/test/midi_clock_slave_test.h
@@ -28,11 +28,11 @@ namespace ARDOUR {
 
 class TestSlaveSessionProxy : public ISlaveSessionProxy {
   #define FRAME_RATE 44100
-  nframes64_t _period_size;
+  framecnt_t _period_size;
 
   double       transport_speed;
-  nframes64_t _transport_frame;
-  nframes64_t _frame_time;
+  framepos_t _transport_frame;
+  framepos_t _frame_time;
   TempoMap    *_tempo_map;
 
   Tempo     tempo;
@@ -53,8 +53,8 @@ class TestSlaveSessionProxy : public ISlaveSessionProxy {
         }
 
         // Controlling the mock object
-        void        set_period_size (nframes64_t a_size) { _period_size = a_size; }
-        nframes64_t period_size () const                 { return _period_size; }
+        void        set_period_size (framecnt_t a_size) { _period_size = a_size; }
+        framecnt_t period_size () const                 { return _period_size; }
         void next_period ()                       { 
           _transport_frame += double(_period_size) * double(transport_speed); 
           _frame_time += _period_size;
@@ -63,12 +63,12 @@ class TestSlaveSessionProxy : public ISlaveSessionProxy {
         // Implementation
   	TempoMap&   tempo_map ()                const { return *_tempo_map; }
 	nframes_t   frame_rate ()               const { return FRAME_RATE; }
-	nframes64_t audible_frame ()            const { return _transport_frame; }
-	nframes64_t transport_frame ()          const { return _transport_frame; }
-	nframes_t   frames_since_cycle_start () const { return 0; }
-	nframes64_t frame_time ()               const { return _frame_time; }
+	framepos_t audible_frame ()            const { return _transport_frame; }
+	framepos_t transport_frame ()          const { return _transport_frame; }
+	nframes_t  frames_since_cycle_start () const { return 0; }
+	framecnt_t frame_time ()               const { return _frame_time; }
 
-	void request_locate (nframes64_t frame, bool with_roll = false) { 
+	void request_locate (framepos_t frame, bool with_roll = false) { 
           _transport_frame = frame; 
         }