diff --git a/src/opus_multistream.c b/src/opus_multistream.c
index 945424fa..a2a48b9a 100644
--- a/src/opus_multistream.c
+++ b/src/opus_multistream.c
@@ -108,7 +108,7 @@ static int get_mono_channel(const ChannelLayout *layout, int stream_id, int prev
    i = (prev<0) ? 0 : prev+1;
    for (;i<layout->nb_channels;i++)
    {
-      if (layout->mapping[i]==2*layout->nb_coupled_streams+stream_id)
+      if (layout->mapping[i]==stream_id+layout->nb_coupled_streams)
          return i;
    }
    return -1;
diff --git a/src/repacketizer.c b/src/repacketizer.c
index 1caa2feb..dd923a21 100644
--- a/src/repacketizer.c
+++ b/src/repacketizer.c
@@ -111,7 +111,7 @@ opus_int32 opus_repacketizer_out_range_impl(OpusRepacketizer *rp, int begin, int
    len = rp->len+begin;
    frames = rp->frames+begin;
    if (self_delimited)
-      tot_size = 1 + len[count-1]>=252;
+      tot_size = 1 + (len[count-1]>=252);
    else
       tot_size = 0;
 
@@ -184,7 +184,6 @@ opus_int32 opus_repacketizer_out_range_impl(OpusRepacketizer *rp, int begin, int
    }
    if (self_delimited) {
       int sdlen = encode_size(len[count-1], data);
-      tot_size += sdlen;
       data += sdlen;
    }
    /* Copy the actual data */