diff --git a/beetsplug/replaygain.py b/beetsplug/replaygain.py
index a618939b8..f9373835f 100644
--- a/beetsplug/replaygain.py
+++ b/beetsplug/replaygain.py
@@ -456,6 +456,7 @@ class FfmpegBackend(Backend):
             "-hide_banner",
             "-i",
             item.path,
+            "-map a:0",
             "-filter",
             "ebur128=peak={0}".format(peak_method),
             "-f",
diff --git a/docs/plugins/replaygain.rst b/docs/plugins/replaygain.rst
index ea119167d..9602618da 100644
--- a/docs/plugins/replaygain.rst
+++ b/docs/plugins/replaygain.rst
@@ -92,7 +92,8 @@ configuration file. The available options are:
 
 - **auto**: Enable ReplayGain analysis during import.
   Default: ``yes``.
-- **backend**: The analysis backend; either ``gstreamer``, ``command``, or ``audiotools``.
+- **backend**: The analysis backend; either ``gstreamer``, ``command``, ``audiotools``
+  or ``ffmpeg``.
   Default: ``command``.
 - **overwrite**: Re-analyze files that already have ReplayGain tags.
   Default: ``no``.