diff --git a/Doc/library/audioop.rst b/Doc/library/audioop.rst
index fbb7fc62944..faf991694de 100644
--- a/Doc/library/audioop.rst
+++ b/Doc/library/audioop.rst
@@ -12,10 +12,8 @@ integers, unless specified otherwise.
 
 .. versionchanged:: 3.4
    Support for 24-bit samples was added.
-
-.. versionchanged:: 3.4
-   Any :term:`bytes-like object`\ s are now accepted by all functions in this
-   module.  Strings no more supported.
+   All functions now accept any :term:`bytes-like object`.
+   String input now results in an immediate error.
 
 .. index::
    single: Intel/DVI ADPCM
diff --git a/Doc/whatsnew/3.4.rst b/Doc/whatsnew/3.4.rst
index d23c3e2fd56..b1930543a8f 100644
--- a/Doc/whatsnew/3.4.rst
+++ b/Doc/whatsnew/3.4.rst
@@ -554,12 +554,16 @@ by Lucas Maystre in :issue:`11175`.)
 audioop
 -------
 
-The module now supports 24-bit samples.  (Contributed by Serhiy Storchaka
+:mod:`audioop` now supports 24-bit samples.  (Contributed by Serhiy Storchaka
 in :issue:`12866`.)
 
 Added the :func:`~audioop.byteswap` function to convert big-endian samples
 to little-endian and vice versa (:issue:`19641`).
 
+All :mod:`audioop` functions now accept any :term:`bytes-like object`.  Strings
+are not accepted: they didn't work before, now they raise an error right away.
+(Contributed by Serhiy Storchaka in :issue:`16685`.)
+
 
 base64
 ------
@@ -2050,6 +2054,9 @@ Changes in the Python API
   matched the input type, so if your code was depending on the return value
   being, say, a ``bytearray``, you will need to change your code.
 
+* :mod:`audioop` functions now raise an error immediately if passed string
+  input, instead of failing randomly later on (:issue:`16685`).
+
 
 Changes in the C API
 --------------------