This patch is an attempt to fix  invalid errors that  stop conversions
involving the AAC audio codec.

--- ffmpeg-2.8.6.old/libavformat/mux.c
+++ ffmpeg-2.8.6/libavformat/mux.c
@@ -538,7 +538,7 @@
     if (st->cur_dts && st->cur_dts != AV_NOPTS_VALUE &&
         ((!(s->oformat->flags & AVFMT_TS_NONSTRICT) &&
           st->codec->codec_type != AVMEDIA_TYPE_SUBTITLE &&
-          st->cur_dts >= pkt->dts) || st->cur_dts > pkt->dts)) {
+          st->cur_dts > pkt->dts) || st->cur_dts > pkt->dts)) {
         av_log(s, AV_LOG_ERROR,
                "Application provided invalid, non monotonically increasing dts to muxer in stream %d: %s >= %s\n",
                st->index, av_ts2str(st->cur_dts), av_ts2str(pkt->dts));