diff --git a/Readme.md b/Readme.md
index 2a6d8d16f..6df4af337 100644
--- a/Readme.md
+++ b/Readme.md
@@ -20,23 +20,24 @@ channelrx:
   - demodlora
   - tcpsrc (although it has evolved please use the udpsrc plugin instead)
 
-<h1>Supported hardware</h1>
+<h1>Specific features</h1>
 
-<h2>General</h2>
-
-<h3>Multiple device support</h3>
+<h2>Multiple device support</h2>
 
 From version 2 SDRangel can integrate more than one hardware device running concurrently.
 
-<h3>Transmission support</h3>
+<h2>Transmission support</h2>
 
-Transmision with "real" devices (BladeRF and HackRF) is supported in Linux versions only
-
-From version 3 transmission or signal generation is supported for BladeRF (HackRF is in the plans for the 3.1 version) using a sample sink plugin:
+From version 3 transmission or signal generation is supported for BladeRF and HackRF (since version 3.1) using a sample sink plugin. These plugins are:
 
   - [BladeRF output plugin](https://github.com/f4exb/sdrangel/tree/dev/plugins/samplesink/bladerfoutput) Linux only
+  - [HackRF output plugin](https://github.com/f4exb/sdrangel/tree/dev/plugins/samplesink/hackrfoutput) Linux only
   - [File output or file sink plugin](https://github.com/f4exb/sdrangel/tree/dev/plugins/samplesink/filesink)
 
+Transmision with "real" devices (BladeRF and HackRF) is supported in Linux versions only. Be also aware that this is **very experimental**. Code is not very efficient so you may experience **performance problems**. Contributions are welcome to enhance the transmission side.
+
+<h1>Supported hardware</h1>
+
 <h2>Airspy</h2>
 
 Airspy is supported through the libairspy library that should be installed in your system for proper build of the software and operation support. Add `libairspy-dev` to the list of dependencies to install.
diff --git a/plugins/samplesink/hackrfoutput/hackrfoutputgui.cpp b/plugins/samplesink/hackrfoutput/hackrfoutputgui.cpp
index 39084c7c9..1420b60a5 100644
--- a/plugins/samplesink/hackrfoutput/hackrfoutputgui.cpp
+++ b/plugins/samplesink/hackrfoutput/hackrfoutputgui.cpp
@@ -297,13 +297,13 @@ void HackRFOutputGui::on_startStop_toggled(bool checked)
         if (m_deviceAPI->initGeneration())
         {
             m_deviceAPI->startGeneration();
-            DSPEngine::instance()->startAudioOutput();
+            DSPEngine::instance()->startAudioInput();
         }
     }
     else
     {
         m_deviceAPI->stopGeneration();
-        DSPEngine::instance()->stopAudioOutput();
+        DSPEngine::instance()->startAudioInput();
     }
 }