Hello team, I filed an issue at https://issues.apache.org/jira/browse/NIFI-4893. I discovered using a complex Avro schema. I've isolated the issue and also did a patch. At least, this solve the issue but actually I don't know well the implications on that solution.
Please let me know what do you think. I have another issue related to Avro and Record, I will file the issue tomorrow. Thanks, Juan