diff --git a/ChangeLog b/ChangeLog
index 991f4012bc..74a4eef6c9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2006-03-02  Michael Smith  <msmith@fluendo.com>
+
+	* ext/amrnb/amrnbenc.c: (gst_amrnbenc_chain):
+	  The AMR encoder writes into the audio buffers it processes, so
+	  use gst_buffer_make_writable() on buffers we might (they go through
+	  an adapter, so there can be copying going on later anyway) be
+	  encoding.
+
 2006-03-01  Tim-Philipp Müller  <tim at centricular dot net>
 
 	* gst/mpegstream/gstmpegparse.c: (gst_mpeg_parse_pad_added),
diff --git a/ext/amrnb/amrnbenc.c b/ext/amrnb/amrnbenc.c
index d82a66c1f2..ad7d14fda3 100644
--- a/ext/amrnb/amrnbenc.c
+++ b/ext/amrnb/amrnbenc.c
@@ -200,6 +200,9 @@ gst_amrnbenc_chain (GstPad * pad, GstBuffer * buffer)
   if (GST_BUFFER_TIMESTAMP_IS_VALID (buffer))
     amrnbenc->ts = GST_BUFFER_TIMESTAMP (buffer);
 
+  /* The AMR encoder actually writes into the source data buffers it gets */
+  buffer = gst_buffer_make_writable (buffer);
+
   ret = GST_FLOW_OK;
   gst_adapter_push (amrnbenc->adapter, buffer);