Dynatrace audit logs indexing problem

Hello, we try to index correctly SecAudit-BackendServer.1.log from Dynatrace however the non-encrypted log files have special characters just before the timestamp : *\x00\x00\x00\xEB\x00\x00\x002018-08-14T16:34:51.920+0200 user=toto,source=1.2.3.4,category=AuditLog,object=,event=Access,status=success,message="successfully read audit log /opt/dynatrace/dynatrace-7.0/log/server/SecAudit-FrontendServer.1.log"* in ssh: ![alt text][1] How would you handle with TIME_PREFIX in props.conf? Thanks. [1]: /storage/temp/255701-capture.png