diff --git a/libavutil/avutil.h b/libavutil/avutil.h
index 8a144a4668d9149250b8301a9358f861aa58df2b..7319c22bfa0c0aaa0cd0c493184c6b8bc095617d 100644
--- a/libavutil/avutil.h
+++ b/libavutil/avutil.h
@@ -153,7 +153,7 @@
 
 #define LIBAVUTIL_VERSION_MAJOR 51
 #define LIBAVUTIL_VERSION_MINOR 27
-#define LIBAVUTIL_VERSION_MICRO  1
+#define LIBAVUTIL_VERSION_MICRO  2
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
                                                LIBAVUTIL_VERSION_MINOR, \
diff --git a/libavutil/samplefmt.c b/libavutil/samplefmt.c
index 761009f2e2ca2c7619eb844deb2fe189a442591f..2e0aa98f582e3a26b4256d714e15503680ff948c 100644
--- a/libavutil/samplefmt.c
+++ b/libavutil/samplefmt.c
@@ -123,6 +123,10 @@ int av_samples_get_buffer_size(int *linesize, int nb_channels, int nb_samples,
     if (!sample_size || nb_samples <= 0 || nb_channels <= 0)
         return AVERROR(EINVAL);
 
+    /* auto-select alignment if not specified */
+    if (!align)
+        align = 32;
+
     /* check for integer overflow */
     if (nb_channels > INT_MAX / align ||
         (int64_t)nb_channels * nb_samples > (INT_MAX - (align * nb_channels)) / sample_size)
diff --git a/libavutil/samplefmt.h b/libavutil/samplefmt.h
index 0d6bde2732fb94e7de34a5007c3a41d37578353b..29a26f0b41efb3e2c32a908280625b7743711681 100644
--- a/libavutil/samplefmt.h
+++ b/libavutil/samplefmt.h
@@ -121,6 +121,7 @@ int av_sample_fmt_is_planar(enum AVSampleFormat sample_fmt);
  * @param nb_channels   the number of channels
  * @param nb_samples    the number of samples in a single channel
  * @param sample_fmt    the sample format
+ * @param align         buffer size alignment (0 = default, 1 = no alignment)
  * @return              required buffer size, or negative error code on failure
  */
 int av_samples_get_buffer_size(int *linesize, int nb_channels, int nb_samples,
@@ -144,7 +145,7 @@ int av_samples_get_buffer_size(int *linesize, int nb_channels, int nb_samples,
  * @param nb_channels      the number of channels
  * @param nb_samples       the number of samples in a single channel
  * @param sample_fmt       the sample format
- * @param align            buffer size alignment (1 = no alignment required)
+ * @param align            buffer size alignment (0 = default, 1 = no alignment)
  * @return                 0 on success or a negative error code on failure
  */
 int av_samples_fill_arrays(uint8_t **audio_data, int *linesize, uint8_t *buf,
@@ -160,7 +161,7 @@ int av_samples_fill_arrays(uint8_t **audio_data, int *linesize, uint8_t *buf,
  * @param[out] linesize    aligned size for audio buffer(s), may be NULL
  * @param nb_channels      number of audio channels
  * @param nb_samples       number of samples per channel
- * @param align            buffer size alignment (1 = no alignment required)
+ * @param align            buffer size alignment (0 = default, 1 = no alignment)
  * @return                 0 on success or a negative error code on failure
  * @see av_samples_fill_arrays()
  */