diff --git a/LArCalorimeter/LArCnv/LArByteStream/python/LArByteStreamConfig.py b/LArCalorimeter/LArCnv/LArByteStream/python/LArByteStreamConfig.py
index 56c50a80186466bb5a1b2e2069906dfa82ce8134..6ea1636676428559381632c704708362ecac09d5 100644
--- a/LArCalorimeter/LArCnv/LArByteStream/python/LArByteStreamConfig.py
+++ b/LArCalorimeter/LArCnv/LArByteStream/python/LArByteStreamConfig.py
@@ -14,7 +14,7 @@ def LArRawDataContByteStreamToolConfig (name="LArRawDataContByteStreamTool",
          from CaloTools.CaloNoiseCondAlg import CaloNoiseCondAlg
          noisealg = CaloNoiseCondAlg ('totalNoise')
          if stream:
-            key = noisealg.OutputKey
+            key = str(noisealg.OutputKey)
             if key.find ('+') < 0:
                key = 'ConditionStore+' + key
             stream.ExtraInputs += [('CaloNoise', key)]