diff --git a/include/osmosdr/osmosdr_source_c.h b/include/osmosdr/osmosdr_source_c.h
index 8410849..9947af7 100644
--- a/include/osmosdr/osmosdr_source_c.h
+++ b/include/osmosdr/osmosdr_source_c.h
@@ -281,6 +281,7 @@ public:
 
   /*!
    * Get the possible bandpass filter settings on the radio frontend.
+   * \param chan the channel index 0 to N-1
    * \return a range of bandwidths in Hz
    */
   virtual osmosdr::meta_range_t get_bandwidth_range( size_t chan = 0 ) = 0;
diff --git a/lib/osmosdr_src_iface.h b/lib/osmosdr_src_iface.h
index d9fa362..f5c7565 100644
--- a/lib/osmosdr_src_iface.h
+++ b/lib/osmosdr_src_iface.h
@@ -223,8 +223,7 @@ public:
    * \param mode iq balance correction mode: 0 = Off, 1 = Manual, 2 = Automatic
    * \param chan the channel index 0 to N-1
    */
-  virtual void set_iq_balance_mode( int mode, size_t chan = 0 )
-    { return; }
+  virtual void set_iq_balance_mode( int mode, size_t chan = 0 ) { }
 
   /*!
    * Set the RX frontend IQ balance correction.
@@ -233,8 +232,7 @@ public:
    * \param correction the complex correction value
    * \param chan the channel index 0 to N-1
    */
-  virtual void set_iq_balance( const std::complex<double> &correction, size_t chan = 0 )
-    { return; }
+  virtual void set_iq_balance( const std::complex<double> &correction, size_t chan = 0 ) { }
 
   /*!
    * Set the bandpass filter on the radio frontend.
@@ -253,10 +251,11 @@ public:
 
   /*!
    * Get the possible bandpass filter settings on the radio frontend.
+   * \param chan the channel index 0 to N-1
    * \return a range of bandwidths in Hz
    */
   virtual osmosdr::meta_range_t get_bandwidth_range( size_t chan = 0 )
-      { return osmosdr::meta_range_t(); }
+    { return osmosdr::meta_range_t(); }
 };
 
 #endif // OSMOSDR_SRC_IFACE_H