diff --git a/gtk2_ardour/engine_dialog.cc b/gtk2_ardour/engine_dialog.cc
index 69580766f3..13e9ac3238 100644
--- a/gtk2_ardour/engine_dialog.cc
+++ b/gtk2_ardour/engine_dialog.cc
@@ -1552,7 +1552,11 @@ EngineControl::set_nperiods_popdown_strings ()
 	vector<string> s;
 
 	if (backend->can_set_period_size()) {
-		np = backend->available_period_sizes (get_driver());
+		if (backend->use_separate_input_and_output_devices ()) {
+			np = backend->available_period_sizes (get_driver(), get_output_device_name ());
+		} else {
+			np = backend->available_period_sizes (get_driver(), get_device_name ());
+		}
 	}
 
 	for (vector<uint32_t>::const_iterator x = np.begin(); x != np.end(); ++x) {
diff --git a/libs/ardour/ardour/audio_backend.h b/libs/ardour/ardour/audio_backend.h
index 1a955336c5..142fff1022 100644
--- a/libs/ardour/ardour/audio_backend.h
+++ b/libs/ardour/ardour/audio_backend.h
@@ -280,7 +280,7 @@ public:
 	}
 
 	/** Returns a vector of supported period-sizes for the given driver */
-	virtual std::vector<uint32_t> available_period_sizes (const std::string& driver) const
+	virtual std::vector<uint32_t> available_period_sizes (const std::string& driver, const std::string& device) const
 	{
 		return std::vector<uint32_t> ();
 	}
diff --git a/libs/ardouralsautil/ardouralsautil/deviceinfo.h b/libs/ardouralsautil/ardouralsautil/deviceinfo.h
index e217a0d575..3ccdb66e8e 100644
--- a/libs/ardouralsautil/ardouralsautil/deviceinfo.h
+++ b/libs/ardouralsautil/ardouralsautil/deviceinfo.h
@@ -24,7 +24,7 @@ namespace ARDOUR {
 	struct ALSADeviceInfo {
 		unsigned int max_channels;
 		unsigned int min_rate, max_rate;
-		unsigned int min_nper, min_nper;
+		unsigned int min_nper, max_nper;
 		unsigned long min_size, max_size;
 		bool valid;
 	};
diff --git a/libs/backends/alsa/alsa_audiobackend.cc b/libs/backends/alsa/alsa_audiobackend.cc
index 6c931b08cb..80b0e36e6f 100644
--- a/libs/backends/alsa/alsa_audiobackend.cc
+++ b/libs/backends/alsa/alsa_audiobackend.cc
@@ -267,11 +267,11 @@ AlsaAudioBackend::available_output_channel_count (const std::string& device) con
 }
 
 std::vector<uint32_t>
-AlsaAudioBackend::available_period_sizes (const std::string& driver) const
+AlsaAudioBackend::available_period_sizes (const std::string& driver, const std::string& device) const
 {
 	std::vector<uint32_t> ps;
 
-	ALSADeviceInfo *nfo = NULL;
+	ALSADeviceInfo* nfo = NULL;
 	if (device == get_standard_device_name(DeviceNone)) {
 		return ps;
 	}
diff --git a/libs/backends/alsa/alsa_audiobackend.h b/libs/backends/alsa/alsa_audiobackend.h
index 02d61c6042..f15c7a2857 100644
--- a/libs/backends/alsa/alsa_audiobackend.h
+++ b/libs/backends/alsa/alsa_audiobackend.h
@@ -140,7 +140,7 @@ class AlsaAudioBackend : public AudioBackend, public PortEngineSharedImpl
 		std::vector<float> available_sample_rates2 (const std::string&, const std::string&) const;
 		std::vector<uint32_t> available_buffer_sizes (const std::string& device) const;
 		std::vector<uint32_t> available_buffer_sizes2 (const std::string&, const std::string&) const;
-		std::vector<uint32_t> available_period_sizes (const std::string& driver) const;
+		std::vector<uint32_t> available_period_sizes (const std::string& driver, const std::string& device) const;
 		uint32_t available_input_channel_count (const std::string& device) const;
 		uint32_t available_output_channel_count (const std::string& device) const;
 
diff --git a/libs/backends/jack/jack_audiobackend.cc b/libs/backends/jack/jack_audiobackend.cc
index 37f5855cf1..89a67e4e0e 100644
--- a/libs/backends/jack/jack_audiobackend.cc
+++ b/libs/backends/jack/jack_audiobackend.cc
@@ -215,7 +215,7 @@ JACKAudioBackend::available_buffer_sizes (const string& device) const
 }
 
 std::vector<uint32_t>
-JACKAudioBackend::available_period_sizes (const std::string& driver) const
+JACKAudioBackend::available_period_sizes (const std::string& driver, const std::string&) const
 {
 	vector<uint32_t> s;
 	if (ARDOUR::get_jack_audio_driver_supports_setting_period_count (driver)) {
diff --git a/libs/backends/jack/jack_audiobackend.h b/libs/backends/jack/jack_audiobackend.h
index 449ad2ffc5..7dfd35572d 100644
--- a/libs/backends/jack/jack_audiobackend.h
+++ b/libs/backends/jack/jack_audiobackend.h
@@ -71,7 +71,7 @@ class JACKAudioBackend : public AudioBackend {
 
     std::vector<float> available_sample_rates (const std::string& device) const;
     std::vector<uint32_t> available_buffer_sizes (const std::string& device) const;
-    std::vector<uint32_t> available_period_sizes (const std::string& driver) const;
+    std::vector<uint32_t> available_period_sizes (const std::string& driver, const std::string& device) const;
     uint32_t available_input_channel_count (const std::string& device) const;
     uint32_t available_output_channel_count (const std::string& device) const;