diff --git a/libavfilter/af_aformat.c b/libavfilter/af_aformat.c
index 3a75b925dd..5b00d7de9c 100644
--- a/libavfilter/af_aformat.c
+++ b/libavfilter/af_aformat.c
@@ -139,8 +139,7 @@ AVFilter avfilter_af_aformat = {
     .priv_size     = sizeof(AFormatContext),
 
     .inputs        = (AVFilterPad[]) {{ .name            = "default",
-                                        .type            = AVMEDIA_TYPE_AUDIO,
-                                        .filter_samples  = ff_null_filter_samples },
+                                        .type            = AVMEDIA_TYPE_AUDIO, },
                                       { .name = NULL}},
     .outputs       = (AVFilterPad[]) {{ .name            = "default",
                                         .type            = AVMEDIA_TYPE_AUDIO},
diff --git a/libavfilter/af_anull.c b/libavfilter/af_anull.c
index 294586e1f3..231fc8c411 100644
--- a/libavfilter/af_anull.c
+++ b/libavfilter/af_anull.c
@@ -33,8 +33,7 @@ AVFilter avfilter_af_anull = {
 
     .inputs    = (AVFilterPad[]) {{ .name             = "default",
                                     .type             = AVMEDIA_TYPE_AUDIO,
-                                    .get_audio_buffer = ff_null_get_audio_buffer,
-                                    .filter_samples   = ff_null_filter_samples },
+                                    .get_audio_buffer = ff_null_get_audio_buffer, },
                                   { .name = NULL}},
 
     .outputs   = (AVFilterPad[]) {{ .name             = "default",
diff --git a/libavfilter/audio.c b/libavfilter/audio.c
index 72e2ced478..14896081a3 100644
--- a/libavfilter/audio.c
+++ b/libavfilter/audio.c
@@ -146,32 +146,12 @@ fail:
     return NULL;
 }
 
-void ff_null_filter_samples(AVFilterLink *link, AVFilterBufferRef *samplesref)
+static void default_filter_samples(AVFilterLink *link,
+                                   AVFilterBufferRef *samplesref)
 {
     ff_filter_samples(link->dst->outputs[0], samplesref);
 }
 
-/* FIXME: samplesref is same as link->cur_buf. Need to consider removing the redundant parameter. */
-void ff_default_filter_samples(AVFilterLink *inlink, AVFilterBufferRef *samplesref)
-{
-    AVFilterLink *outlink = NULL;
-
-    if (inlink->dst->nb_outputs)
-        outlink = inlink->dst->outputs[0];
-
-    if (outlink) {
-        outlink->out_buf = ff_default_get_audio_buffer(inlink, AV_PERM_WRITE,
-                                                       samplesref->audio->nb_samples);
-        outlink->out_buf->pts                = samplesref->pts;
-        outlink->out_buf->audio->sample_rate = samplesref->audio->sample_rate;
-        ff_filter_samples(outlink, avfilter_ref_buffer(outlink->out_buf, ~0));
-        avfilter_unref_buffer(outlink->out_buf);
-        outlink->out_buf = NULL;
-    }
-    avfilter_unref_buffer(samplesref);
-    inlink->cur_buf = NULL;
-}
-
 void ff_filter_samples(AVFilterLink *link, AVFilterBufferRef *samplesref)
 {
     void (*filter_samples)(AVFilterLink *, AVFilterBufferRef *);
@@ -181,7 +161,7 @@ void ff_filter_samples(AVFilterLink *link, AVFilterBufferRef *samplesref)
     FF_DPRINTF_START(NULL, filter_samples); ff_dlog_link(NULL, link, 1);
 
     if (!(filter_samples = dst->filter_samples))
-        filter_samples = ff_default_filter_samples;
+        filter_samples = default_filter_samples;
 
     /* prepare to copy the samples if the buffer has insufficient permissions */
     if ((dst->min_perms & samplesref->perms) != dst->min_perms ||
diff --git a/libavfilter/audio.h b/libavfilter/audio.h
index 935bec5c43..9af44f8a1c 100644
--- a/libavfilter/audio.h
+++ b/libavfilter/audio.h
@@ -42,12 +42,6 @@ AVFilterBufferRef *ff_null_get_audio_buffer(AVFilterLink *link, int perms,
 AVFilterBufferRef *ff_get_audio_buffer(AVFilterLink *link, int perms,
                                              int nb_samples);
 
-/** default handler for filter_samples() for audio inputs */
-void ff_default_filter_samples(AVFilterLink *link, AVFilterBufferRef *samplesref);
-
-/** filter_samples() handler for filters which simply pass audio along */
-void ff_null_filter_samples(AVFilterLink *link, AVFilterBufferRef *samplesref);
-
 /**
  * Send a buffer of audio samples to the next filter.
  *