diff --git a/libavcodec/adpcm.c b/libavcodec/adpcm.c
index 8184378a16..4d2146f23a 100644
--- a/libavcodec/adpcm.c
+++ b/libavcodec/adpcm.c
@@ -648,14 +648,11 @@ static int adpcm_encode_frame(AVCodecContext *avctx,
                     *dst++ = buf[0][i] | (buf[1][i] << 4);
             }
         } else
-        for (; n>0; n--) {
-            for(i = 0; i < avctx->channels; i++) {
-                int nibble;
-                nibble  = adpcm_yamaha_compress_sample(&c->status[i], samples[i]);
-                nibble |= adpcm_yamaha_compress_sample(&c->status[i], samples[i+avctx->channels]) << 4;
-                *dst++ = nibble;
-            }
-            samples += 2 * avctx->channels;
+        for (n *= avctx->channels; n>0; n--) {
+            int nibble;
+            nibble  = adpcm_yamaha_compress_sample(&c->status[ 0], *samples++);
+            nibble |= adpcm_yamaha_compress_sample(&c->status[st], *samples++) << 4;
+            *dst++ = nibble;
         }
         break;
     default:
diff --git a/tests/rotozoom.regression.ref b/tests/rotozoom.regression.ref
index 99f077725f..d7060639c5 100644
--- a/tests/rotozoom.regression.ref
+++ b/tests/rotozoom.regression.ref
@@ -193,10 +193,10 @@ stddev:  914.63 PSNR: 37.09 bytes:  1058604/  1058444
 268344 ./tests/data/a-adpcm_ms.wav
 7be370f937c51e8a967e6a3d08d5156a *./tests/data/adpcm_ms.rotozoom.out.wav
 stddev: 1050.00 PSNR: 35.90 bytes:  1060620/  1058444
-14df8b8bb7c127ec70c0167df1c0dbf7 *./tests/data/a-adpcm_yam.wav
+2546d72df736b5ffa1557e8c9c9ef788 *./tests/data/a-adpcm_yam.wav
 266296 ./tests/data/a-adpcm_yam.wav
-2f73107dafef6db42e545f9e466d3f05 *./tests/data/adpcm_yam.rotozoom.out.wav
-stddev:18302.45 PSNR: 11.07 bytes:  1065004/  1058444
+c80c847a53a0fee17a88fa889ec34a4e *./tests/data/adpcm_yam.rotozoom.out.wav
+stddev: 1247.64 PSNR: 34.40 bytes:  1065004/  1058444
 42d4639866ed4d692eaf126228a4fa2a *./tests/data/a-adpcm_swf.flv
 269166 ./tests/data/a-adpcm_swf.flv
 628089745a7059ae4055c2515b6d668b *./tests/data/adpcm_swf.rotozoom.out.wav
diff --git a/tests/vsynth.regression.ref b/tests/vsynth.regression.ref
index dd4f4733c9..9a671c9b58 100644
--- a/tests/vsynth.regression.ref
+++ b/tests/vsynth.regression.ref
@@ -193,10 +193,10 @@ stddev:  914.63 PSNR: 37.09 bytes:  1058604/  1058444
 268344 ./tests/data/a-adpcm_ms.wav
 7be370f937c51e8a967e6a3d08d5156a *./tests/data/adpcm_ms.vsynth.out.wav
 stddev: 1050.00 PSNR: 35.90 bytes:  1060620/  1058444
-14df8b8bb7c127ec70c0167df1c0dbf7 *./tests/data/a-adpcm_yam.wav
+2546d72df736b5ffa1557e8c9c9ef788 *./tests/data/a-adpcm_yam.wav
 266296 ./tests/data/a-adpcm_yam.wav
-2f73107dafef6db42e545f9e466d3f05 *./tests/data/adpcm_yam.vsynth.out.wav
-stddev:18302.45 PSNR: 11.07 bytes:  1065004/  1058444
+c80c847a53a0fee17a88fa889ec34a4e *./tests/data/adpcm_yam.vsynth.out.wav
+stddev: 1247.64 PSNR: 34.40 bytes:  1065004/  1058444
 42d4639866ed4d692eaf126228a4fa2a *./tests/data/a-adpcm_swf.flv
 269166 ./tests/data/a-adpcm_swf.flv
 628089745a7059ae4055c2515b6d668b *./tests/data/adpcm_swf.vsynth.out.wav