autodiscovery adding _hostname to database target names

Hello,

I'm setting up OEM12c agents and when I do the autodiscovery for a host, some of the discovered database targets have a discovered name of <databasename> whereas some have <databasename>_<hostname>.  We would like all of our database targets to be named with the same convention.  I have the ability to change the name prior to promoting the target, but I'd like to know why it is doing this & if there is a way to make it consistent. 

Anybody ever run into this?

Thanks!