diff --git a/beets/library.py b/beets/library.py
index 3cdc713bb..a56575a52 100644
--- a/beets/library.py
+++ b/beets/library.py
@@ -522,8 +522,8 @@ class Item(LibModel):
         'rg_track_peak': types.NULL_FLOAT,
         'rg_album_gain': types.NULL_FLOAT,
         'rg_album_peak': types.NULL_FLOAT,
-        'r128_track_gain': types.NullPaddedInt(6),
-        'r128_album_gain': types.NullPaddedInt(6),
+        'r128_track_gain': types.NULL_FLOAT,
+        'r128_album_gain': types.NULL_FLOAT,
         'original_year': types.PaddedInt(4),
         'original_month': types.PaddedInt(2),
         'original_day': types.PaddedInt(2),
@@ -1071,7 +1071,7 @@ class Album(LibModel):
         'releasegroupdisambig': types.STRING,
         'rg_album_gain': types.NULL_FLOAT,
         'rg_album_peak': types.NULL_FLOAT,
-        'r128_album_gain': types.NullPaddedInt(6),
+        'r128_album_gain': types.NULL_FLOAT,
         'original_year': types.PaddedInt(4),
         'original_month': types.PaddedInt(2),
         'original_day': types.PaddedInt(2),
diff --git a/docs/changelog.rst b/docs/changelog.rst
index 8d95b7fb0..3dd225864 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -11,6 +11,10 @@ Bug fixes:
 * :doc:`/plugins/lyrics`: Fix Genius search by using query params instead of body.
 * :doc:`/plugins/unimported`: The new ``ignore_subdirectories`` configuration
   option added in 1.6.0 now has a default value if it hasn't been set.
+* :doc:`/plugins/replaygain`: The type of the internal ``r128_track_gain`` and
+  ``r128_album_gain`` fields was changed from integer to float to fix loss of
+  precision due to truncation.
+  :bug:`4169`
 
 For packagers: