commit 3acbb4375ffe8a07b6f8aa51dd6d1bbb541208d6
Author: Stéphane Cerveau <scerveau@connected-labs.com>
Date:   Wed Jun 24 10:59:03 2015 +0200

    flacdec: metadata detection
    
    Unable the set format if the metadata detection fails.

diff --git a/ext/flac/gstflacdec.c b/ext/flac/gstflacdec.c
index 49436dd..3ac8730 100644
--- a/ext/flac/gstflacdec.c
+++ b/ext/flac/gstflacdec.c
@@ -275,6 +275,7 @@ gst_flac_dec_set_format (GstAudioDecoder * dec, GstCaps * caps)
   GST_DEBUG_OBJECT (dec, "Processing headers and metadata");
   if (!FLAC__stream_decoder_process_until_end_of_metadata (flacdec->decoder)) {
     GST_WARNING_OBJECT (dec, "process_until_end_of_metadata failed");
+    return FALSE;
   }
   GST_INFO_OBJECT (dec, "headers and metadata are now processed");
   return TRUE;
