diff --git a/apps/osmosdr_source.grc b/apps/osmosdr_source.grc
index 2a22589..03e439a 100644
--- a/apps/osmosdr_source.grc
+++ b/apps/osmosdr_source.grc
@@ -1,6 +1,6 @@
 <?xml version='1.0' encoding='ASCII'?>
 <flow_graph>
-  <timestamp>Sat May  5 14:59:24 2012</timestamp>
+  <timestamp>Sat May  5 21:04:19 2012</timestamp>
   <block>
     <key>options</key>
     <param>
@@ -426,7 +426,7 @@
     </param>
     <param>
       <key>args</key>
-      <value>rtl=0</value>
+      <value></value>
     </param>
     <param>
       <key>nchan</key>
@@ -450,7 +450,7 @@
     </param>
     <param>
       <key>gain_mode0</key>
-      <value>1</value>
+      <value>0</value>
     </param>
     <param>
       <key>ant0</key>
@@ -470,7 +470,7 @@
     </param>
     <param>
       <key>gain_mode1</key>
-      <value>1</value>
+      <value>0</value>
     </param>
     <param>
       <key>ant1</key>
diff --git a/apps/osmosdr_source_multi.grc b/apps/osmosdr_source_multi.grc
index dc14239..7270485 100644
--- a/apps/osmosdr_source_multi.grc
+++ b/apps/osmosdr_source_multi.grc
@@ -1,6 +1,6 @@
 <?xml version='1.0' encoding='ASCII'?>
 <flow_graph>
-  <timestamp>Sat Apr 28 20:02:00 2012</timestamp>
+  <timestamp>Sat May  5 21:02:25 2012</timestamp>
   <block>
     <key>options</key>
     <param>
@@ -43,6 +43,10 @@
       <key>run</key>
       <value>True</value>
     </param>
+    <param>
+      <key>max_nouts</key>
+      <value>0</value>
+    </param>
     <param>
       <key>realtime_scheduling</key>
       <value></value>
@@ -56,61 +60,6 @@
       <value>0</value>
     </param>
   </block>
-  <block>
-    <key>variable_slider</key>
-    <param>
-      <key>id</key>
-      <value>gain</value>
-    </param>
-    <param>
-      <key>_enabled</key>
-      <value>True</value>
-    </param>
-    <param>
-      <key>label</key>
-      <value></value>
-    </param>
-    <param>
-      <key>value</key>
-      <value>10</value>
-    </param>
-    <param>
-      <key>min</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>max</key>
-      <value>30</value>
-    </param>
-    <param>
-      <key>num_steps</key>
-      <value>31</value>
-    </param>
-    <param>
-      <key>style</key>
-      <value>wx.SL_HORIZONTAL</value>
-    </param>
-    <param>
-      <key>converver</key>
-      <value>float_converter</value>
-    </param>
-    <param>
-      <key>grid_pos</key>
-      <value></value>
-    </param>
-    <param>
-      <key>notebook</key>
-      <value></value>
-    </param>
-    <param>
-      <key>_coordinate</key>
-      <value>(472, 65)</value>
-    </param>
-    <param>
-      <key>_rotation</key>
-      <value>0</value>
-    </param>
-  </block>
   <block>
     <key>variable</key>
     <param>
@@ -418,6 +367,57 @@
       <value>0</value>
     </param>
   </block>
+  <block>
+    <key>variable_chooser</key>
+    <param>
+      <key>id</key>
+      <value>gain_chooser</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>label</key>
+      <value></value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>9.0</value>
+    </param>
+    <param>
+      <key>choices</key>
+      <value>[-1.0, 1.5, 4.0, 6.5, 9.0, 11.5, 14.0, 16.5, 19.0, 21.5, 24.0, 29.0, 34.0, 42.0, 43.0, 45.0, 47.0, 49.0]</value>
+    </param>
+    <param>
+      <key>labels</key>
+      <value>[]</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>drop_down</value>
+    </param>
+    <param>
+      <key>style</key>
+      <value>wx.RA_HORIZONTAL</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(460, 64)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
   <block>
     <key>osmosdr_source_c</key>
     <param>
@@ -454,7 +454,11 @@
     </param>
     <param>
       <key>gain0</key>
-      <value>gain</value>
+      <value>gain_chooser</value>
+    </param>
+    <param>
+      <key>gain_mode0</key>
+      <value>0</value>
     </param>
     <param>
       <key>ant0</key>
@@ -470,7 +474,11 @@
     </param>
     <param>
       <key>gain1</key>
-      <value>gain</value>
+      <value>gain_chooser</value>
+    </param>
+    <param>
+      <key>gain_mode1</key>
+      <value>0</value>
     </param>
     <param>
       <key>ant1</key>
@@ -488,6 +496,10 @@
       <key>gain2</key>
       <value>0</value>
     </param>
+    <param>
+      <key>gain_mode2</key>
+      <value>0</value>
+    </param>
     <param>
       <key>ant2</key>
       <value></value>
@@ -504,6 +516,10 @@
       <key>gain3</key>
       <value>0</value>
     </param>
+    <param>
+      <key>gain_mode3</key>
+      <value>0</value>
+    </param>
     <param>
       <key>ant3</key>
       <value></value>
@@ -520,6 +536,10 @@
       <key>gain4</key>
       <value>0</value>
     </param>
+    <param>
+      <key>gain_mode4</key>
+      <value>0</value>
+    </param>
     <param>
       <key>ant4</key>
       <value></value>
diff --git a/grc/gen_osmosdr_blocks.py b/grc/gen_osmosdr_blocks.py
index b57fa16..5c831c2 100644
--- a/grc/gen_osmosdr_blocks.py
+++ b/grc/gen_osmosdr_blocks.py
@@ -180,11 +180,11 @@ PARAMS_TMPL = """
 		<hide>\#if \$nchan() > $n then 'none' else 'all'#</hide>
 		<option>
 			<name>Manual</name>
-			<key>1</key>
+			<key>0</key>
 		</option>
 		<option>
 			<name>Auto</name>
-			<key>0</key>
+			<key>1</key>
 		</option>
 	</param>
 	<param>
diff --git a/include/osmosdr/osmosdr_source_c.h b/include/osmosdr/osmosdr_source_c.h
index fae0f05..1da922b 100644
--- a/include/osmosdr/osmosdr_source_c.h
+++ b/include/osmosdr/osmosdr_source_c.h
@@ -148,7 +148,7 @@ public:
   /*!
    * Set the gain mode for the underlying radio hardware.
    * This might be supported only for certain hardware types.
-   * \param mode the gain mode (true means manual gain mode)
+   * \param mode the gain mode (true means automatic gain mode)
    * \param chan the channel index 0 to N-1
    * \return the actual gain mode
    */
diff --git a/lib/osmosdr_src_iface.h b/lib/osmosdr_src_iface.h
index 2a6ae40..a02e8c1 100644
--- a/lib/osmosdr_src_iface.h
+++ b/lib/osmosdr_src_iface.h
@@ -126,7 +126,7 @@ public:
   /*!
    * Set the gain mode for the underlying radio hardware.
    * This might be supported only for certain hardware types.
-   * \param mode the gain mode (true means manual gain mode)
+   * \param mode the gain mode (true means automatic gain mode)
    * \param chan the channel index 0 to N-1
    * \return the actual gain mode
    */
diff --git a/lib/rtl/rtl_source_c.cc b/lib/rtl/rtl_source_c.cc
index f60d2cf..c594abc 100644
--- a/lib/rtl/rtl_source_c.cc
+++ b/lib/rtl/rtl_source_c.cc
@@ -153,9 +153,13 @@ rtl_source_c::rtl_source_c (const std::string &args)
   if (ret < 0)
       throw std::runtime_error("Failed to reset usb buffers.");
 
+  ret = rtlsdr_set_tuner_gain_mode(_dev, 1);
+  if (ret < 0)
+      throw std::runtime_error("Failed to enable manual gain mode.");
+
   _running = true;
 
-  _manual_gain = false;
+  _auto_gain = false;
 
   _thread = gruel::thread(_rtlsdr_wait, this);
 }
@@ -418,8 +422,8 @@ osmosdr::gain_range_t rtl_source_c::get_gain_range( const std::string & name, si
 bool rtl_source_c::set_gain_mode( bool mode, size_t chan )
 {
   if (_dev) {
-    if (!rtlsdr_set_tuner_gain_mode(_dev, int(mode))) {
-      _manual_gain = mode;
+    if (!rtlsdr_set_tuner_gain_mode(_dev, int(!mode))) {
+      _auto_gain = mode;
     }
   }
 
@@ -428,7 +432,7 @@ bool rtl_source_c::set_gain_mode( bool mode, size_t chan )
 
 bool rtl_source_c::get_gain_mode( size_t chan )
 {
-  return _manual_gain;
+  return _auto_gain;
 }
 
 double rtl_source_c::set_gain( double gain, size_t chan )
diff --git a/lib/rtl/rtl_source_c.h b/lib/rtl/rtl_source_c.h
index b2591f1..737e3c0 100644
--- a/lib/rtl/rtl_source_c.h
+++ b/lib/rtl/rtl_source_c.h
@@ -132,7 +132,7 @@ private:
   unsigned int _buf_offset;
   unsigned int _samp_avail;
 
-  bool _manual_gain;
+  bool _auto_gain;
 };
 
 #endif /* INCLUDED_RTLSDR_SOURCE_C_H */