diff --git a/include/osmosdr/sink.h b/include/osmosdr/sink.h
index a4b52c4..10c9038 100644
--- a/include/osmosdr/sink.h
+++ b/include/osmosdr/sink.h
@@ -254,7 +254,7 @@ public:
 
   /*!
    * Set the bandpass filter on the radio frontend.
-   * \param bandwidth the filter bandwidth in Hz
+   * \param bandwidth the filter bandwidth in Hz, set to 0 for automatic selection
    * \param chan the channel index 0 to N-1
    * \return the actual filter bandwidth in Hz
    */
diff --git a/include/osmosdr/source.h b/include/osmosdr/source.h
index 081c6de..ca718e8 100644
--- a/include/osmosdr/source.h
+++ b/include/osmosdr/source.h
@@ -289,7 +289,7 @@ public:
 
   /*!
    * Set the bandpass filter on the radio frontend.
-   * \param bandwidth the filter bandwidth in Hz
+   * \param bandwidth the filter bandwidth in Hz, set to 0 for automatic selection
    * \param chan the channel index 0 to N-1
    * \return the actual filter bandwidth in Hz
    */
diff --git a/lib/sink_iface.h b/lib/sink_iface.h
index 9f06537..49eea7b 100644
--- a/lib/sink_iface.h
+++ b/lib/sink_iface.h
@@ -233,7 +233,7 @@ public:
 
   /*!
    * Set the bandpass filter on the radio frontend.
-   * \param bandwidth the filter bandwidth in Hz
+   * \param bandwidth the filter bandwidth in Hz, set to 0 for automatic selection
    * \param chan the channel index 0 to N-1
    * \return the actual filter bandwidth in Hz
    */
diff --git a/lib/source_iface.h b/lib/source_iface.h
index 41beee5..659a702 100644
--- a/lib/source_iface.h
+++ b/lib/source_iface.h
@@ -256,7 +256,7 @@ public:
 
   /*!
    * Set the bandpass filter on the radio frontend.
-   * \param bandwidth the filter bandwidth in Hz
+   * \param bandwidth the filter bandwidth in Hz, set to 0 for automatic selection
    * \param chan the channel index 0 to N-1
    * \return the actual filter bandwidth in Hz
    */