diff --git a/libavcodec/apedec.c b/libavcodec/apedec.c
index 82d567f4cfcf560403f6ff2d312888c448f32084..8746724133ab766f7acd779a557c74015ffa4e00 100644
--- a/libavcodec/apedec.c
+++ b/libavcodec/apedec.c
@@ -199,6 +199,7 @@ static av_cold int ape_decode_init(AVCodecContext * avctx)
 
     dsputil_init(&s->dsp, avctx);
     avctx->sample_fmt = SAMPLE_FMT_S16;
+    avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
     return 0;
 }
 
diff --git a/libavcodec/mpc7.c b/libavcodec/mpc7.c
index 565b8589eceef0ae40c2a2aac1421624612080fe..2db417280ccd8426e592307822f41e921d8b8ac2 100644
--- a/libavcodec/mpc7.c
+++ b/libavcodec/mpc7.c
@@ -109,6 +109,7 @@ static av_cold int mpc7_decode_init(AVCodecContext * avctx)
     }
     vlc_initialized = 1;
     avctx->sample_fmt = SAMPLE_FMT_S16;
+    avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
     return 0;
 }
 
diff --git a/libavcodec/mpc8.c b/libavcodec/mpc8.c
index 0d4f12891208787daf271ddc4093edb78ef713b9..c47e74dde2120d67da1bb38606134c9de91b442e 100644
--- a/libavcodec/mpc8.c
+++ b/libavcodec/mpc8.c
@@ -178,6 +178,7 @@ static av_cold int mpc8_decode_init(AVCodecContext * avctx)
     }
     vlc_initialized = 1;
     avctx->sample_fmt = SAMPLE_FMT_S16;
+    avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
     return 0;
 }
 
diff --git a/libavcodec/smacker.c b/libavcodec/smacker.c
index 1690518b6b17483bec27e5442768a423c415664e..5de3769e3c635dedcc7cebb251aadfee89764870 100644
--- a/libavcodec/smacker.c
+++ b/libavcodec/smacker.c
@@ -559,6 +559,7 @@ static av_cold int decode_end(AVCodecContext *avctx)
 static av_cold int smka_decode_init(AVCodecContext *avctx)
 {
     avctx->sample_fmt = SAMPLE_FMT_S16;
+    avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
     return 0;
 }
 
diff --git a/libavcodec/wavpack.c b/libavcodec/wavpack.c
index e8703b38dce26354eddb7c4d0a7a2c8e33d44e18..b89723e2f23dc32403a49d8ef2b9536c81893471 100644
--- a/libavcodec/wavpack.c
+++ b/libavcodec/wavpack.c
@@ -361,6 +361,7 @@ static av_cold int wavpack_decode_init(AVCodecContext *avctx)
     s->avctx = avctx;
     s->stereo = (avctx->channels == 2);
     avctx->sample_fmt = SAMPLE_FMT_S16;
+    avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
 
     return 0;
 }