diff --git a/wavinfo/riff_parser.py b/wavinfo/riff_parser.py
index 5a0d523..5a941dd 100644
--- a/wavinfo/riff_parser.py
+++ b/wavinfo/riff_parser.py
@@ -57,7 +57,7 @@ def parse_chunk(stream, rf64_context=None):
 
     if data_size == 0xFFFFFFFF:
         if rf64_context is None and ident in [b'RF64', b'BW64']:
-            rf64_context = parse_rf64(stream=stream)
+            rf64_context = parse_rf64(stream=stream, signature=ident)
 
         data_size = rf64_context.bigchunk_table[ident]