diff --git a/tabellio/pfbviews/comevent.py b/tabellio/pfbviews/comevent.py
index 07039f6..49ec9c5 100644
--- a/tabellio/pfbviews/comevent.py
+++ b/tabellio/pfbviews/comevent.py
@@ -6,6 +6,8 @@ import tabellio.config.utils
 
 class CommissionView(ParlEventBaseView):
     def get_stream_name(self):
+        if not self.context.commission:
+            return 'XXXX'
         com_id = self.context.commission.to_path.split('/')[-1]
         com_audio_code = tabellio.config.utils.get_com_audio_code(com_id)
         filename = '%04d%02d%02d%02d-%s.mp3' % (