vorbis: avoid invalid free

Regression started at commit "4b67376 Remove multiple subtly different inline..."

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/info.c b/lib/info.c
index 971f004a..fe759edf 100644
--- a/lib/info.c
+++ b/lib/info.c
@@ -647,7 +647,7 @@ int vorbis_analysis_headerout(vorbis_dsp_state *v,
   memset(op_code,0,sizeof(*op_code));
 
   if(b){
-    oggpack_writeclear(&opb);
+    if(vi->channels>0)oggpack_writeclear(&opb);
     if(b->header)_ogg_free(b->header);
     if(b->header1)_ogg_free(b->header1);
     if(b->header2)_ogg_free(b->header2);