diff --git a/libavcodec/ttaenc.c b/libavcodec/ttaenc.c
index c77e0c29b0b6d989e08d8fe00afcef53c337c7bd..55599cc525ad9f42e97e06e0ee606320c90fa242 100644
--- a/libavcodec/ttaenc.c
+++ b/libavcodec/ttaenc.c
@@ -116,7 +116,7 @@ static int tta_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
     PutBitContext pb;
     int ret, i, out_bytes, cur_chan = 0, res = 0, samples = 0;
 
-    if ((ret = ff_alloc_packet2(avctx, avpkt, frame->nb_samples * 2 * s->bps)) < 0)
+    if ((ret = ff_alloc_packet2(avctx, avpkt, frame->nb_samples * 2 * avctx->channels * s->bps)) < 0)
         return ret;
     init_put_bits(&pb, avpkt->data, avpkt->size);