diff --git a/libavcodec/wmaenc.c b/libavcodec/wmaenc.c
index f1b5529d2f5212ec2f4a482890b84e3e5908b6e5..4fe3083b8c72796e71d99a816940cb9445fa028c 100644
--- a/libavcodec/wmaenc.c
+++ b/libavcodec/wmaenc.c
@@ -36,6 +36,9 @@ static int encode_init(AVCodecContext * avctx){
     if(avctx->channels > MAX_CHANNELS)
         return -1;
 
+    if(avctx->bit_rate < 24*1000)
+        return -1;
+
     /* extract flag infos */
     flags1 = 0;
     flags2 = 1;