@@ -199,6 +199,8 @@ static int output_configure(AACContext *ac, enum ChannelPosition che_pos[4][MAX_

     avctx->channels = channels;

+    ac->output_configured = 1;

+

     return 0;

 }

@@ -445,12 +447,6 @@ static av_cold int aac_decode_init(AVCodecContext * avccontext) {

             return -1;

         avccontext->sample_rate = ac->m4ac.sample_rate;

     } else if (avccontext->channels > 0) {

-        enum ChannelPosition new_che_pos[4][MAX_ELEM_ID];

-        memset(new_che_pos, 0, 4 * MAX_ELEM_ID * sizeof(new_che_pos[0][0]));

-        if(set_default_channel_config(ac, new_che_pos, avccontext->channels - (avccontext->channels == 8)))

-            return -1;

-        if(output_configure(ac, ac->che_pos, new_che_pos, 1))

-            return -1;

         ac->m4ac.sample_rate = avccontext->sample_rate;

     }

@@ -1579,8 +1575,15 @@ static int parse_adts_frame_header(AACContext * ac, GetBitContext * gb) {

     size = ff_aac_parse_header(gb, &hdr_info);

     if (size > 0) {

-        if (hdr_info.chan_config)

+        if (!ac->output_configured && hdr_info.chan_config) {

+            enum ChannelPosition new_che_pos[4][MAX_ELEM_ID];

+            memset(new_che_pos, 0, 4 * MAX_ELEM_ID * sizeof(new_che_pos[0][0]));

             ac->m4ac.chan_config = hdr_info.chan_config;

+            if (set_default_channel_config(ac, new_che_pos, hdr_info.chan_config))

+                return -7;

+            if (output_configure(ac, ac->che_pos, new_che_pos, 1))

+                return -7;

+        }

         ac->m4ac.sample_rate     = hdr_info.sample_rate;

         ac->m4ac.sampling_index  = hdr_info.sampling_index;

         ac->m4ac.object_type     = hdr_info.object_type;

@@ -1655,6 +1658,10 @@ static int aac_decode_frame(AVCodecContext * avccontext, void * data, int * data

             memset(new_che_pos, 0, 4 * MAX_ELEM_ID * sizeof(new_che_pos[0][0]));

             if((err = decode_pce(ac, new_che_pos, &gb)))

                 break;

+            if (ac->output_configured)

+                av_log(avccontext, AV_LOG_ERROR,

+                       "Not evaluating a further program_config_element as this construct is dubious at best.\n");

+            else

             err = output_configure(ac, ac->che_pos, new_che_pos, 0);

             break;

         }

@@ -274,6 +274,8 @@ typedef struct {

     /** @} */

     DECLARE_ALIGNED(16, float, temp[128]);

+

+    int output_configured;

 } AACContext;

 #endif /* AVCODEC_AAC_H */