diff -Nraub mplayer.ori/libmpcodecs/ae_lavc.c mplayer/libmpcodecs/ae_lavc.c
--- mplayer.ori/libmpcodecs/ae_lavc.c	2006-09-12 11:58:52.000000000 -0400
+++ mplayer/libmpcodecs/ae_lavc.c	2006-10-13 22:54:47.000000000 -0400
@@ -102,6 +102,17 @@
 static int encode_lavc(audio_encoder_t *encoder, uint8_t *dest, void *src, int size, int max_size)
 {
 	int n;
+    if (encoder->params.channels == 6 || encoder->params.channels == 5) {
+        //Codec wants: L C R  SL SR LFE
+        //We have:     L R SL SR C  LFE
+        int i;
+        uint16_t tmp;
+        for (i = 0; i < size; i += encoder->params.channels*2) {
+            tmp = ((uint16_t*)(src+i))[4];
+            memmove(src+i+4, src+i+2, 3*2);
+            ((uint16_t*)(src+i))[1] = tmp;
+        }
+    }
 	n = avcodec_encode_audio(lavc_actx, dest, size, src);
         compressed_frame_size = n;
 	return n;