diff --git a/devices/hackrf/devicehackrfshared.cpp b/devices/hackrf/devicehackrfshared.cpp
index aa7092369..c29372074 100644
--- a/devices/hackrf/devicehackrfshared.cpp
+++ b/devices/hackrf/devicehackrfshared.cpp
@@ -18,4 +18,5 @@
 
 MESSAGE_CLASS_DEFINITION(DeviceHackRFShared::MsgConfigureFrequencyDelta, Message)
 
-
+const float  DeviceHackRFShared::m_sampleFifoLengthInSeconds = 0.25;
+const int    DeviceHackRFShared::m_sampleFifoMinSize = 150000; // 600kS/s knee
diff --git a/devices/hackrf/devicehackrfshared.h b/devices/hackrf/devicehackrfshared.h
index 824d97798..f9106a8d3 100644
--- a/devices/hackrf/devicehackrfshared.h
+++ b/devices/hackrf/devicehackrfshared.h
@@ -42,6 +42,9 @@ public:
             m_frequencyDelta(frequencyDelta)
         { }
     };
+
+    static const float  m_sampleFifoLengthInSeconds;
+    static const int    m_sampleFifoMinSize;
 };
 
 
diff --git a/devices/limesdr/devicelimesdrshared.cpp b/devices/limesdr/devicelimesdrshared.cpp
index ed445e271..0dd63bbea 100644
--- a/devices/limesdr/devicelimesdrshared.cpp
+++ b/devices/limesdr/devicelimesdrshared.cpp
@@ -20,4 +20,4 @@ MESSAGE_CLASS_DEFINITION(DeviceLimeSDRShared::MsgCrossReportToGUI, Message)
 MESSAGE_CLASS_DEFINITION(DeviceLimeSDRShared::MsgReportDeviceInfo, Message)
 
 const float  DeviceLimeSDRShared::m_sampleFifoLengthInSeconds = 0.25;
-const int    DeviceLimeSDRShared::m_sampleFifoMinSize = 48000;
+const int    DeviceLimeSDRShared::m_sampleFifoMinSize = 48000; // 192kS/s knee
diff --git a/plugins/samplesink/hackrfoutput/hackrfoutput.cpp b/plugins/samplesink/hackrfoutput/hackrfoutput.cpp
index 32ab87fa9..c228ca4e5 100644
--- a/plugins/samplesink/hackrfoutput/hackrfoutput.cpp
+++ b/plugins/samplesink/hackrfoutput/hackrfoutput.cpp
@@ -25,7 +25,7 @@
 #include "dsp/dspengine.h"
 #include "device/devicesourceapi.h"
 #include "device/devicesinkapi.h"
-
+#include "hackrf/devicehackrfshared.h"
 
 #include "hackrfoutputgui.h"
 #include "hackrfoutputthread.h"
@@ -242,11 +242,10 @@ bool HackRFOutput::applySettings(const HackRFOutputSettings& settings, bool forc
     if ((m_settings.m_devSampleRate != settings.m_devSampleRate) || (m_settings.m_log2Interp != settings.m_log2Interp) || force)
     {
         forwardChange = true;
-
-        // FIFO size:
-        // 1 s length up to interpolation by 16
-        // 2 s for interpolation by 32
-        m_sampleSourceFifo.resize(settings.m_devSampleRate/(1<<(settings.m_log2Interp <= 4 ? settings.m_log2Interp : 4)));
+        int fifoSize = std::max(
+                (int) ((settings.m_devSampleRate/(1<<settings.m_log2Interp)) * DeviceHackRFShared::m_sampleFifoLengthInSeconds),
+                DeviceHackRFShared::m_sampleFifoMinSize);
+        m_sampleSourceFifo.resize(fifoSize);
     }
 
 	if ((m_settings.m_devSampleRate != settings.m_devSampleRate) || force)