IMPORT EDI process does not create Epicor order, even though log states it did

The IMPORT EDI process sometimes does not create an Epicor order at times, even though the EDI log states that the order was created OK.  We noticed that this happens when 2 Import EDI logs are generated for the same Import EDI process run, which I believe Epicor is launching 2 threads for some reason.  Has anyone else had this problem? Is there a way to tell Epicor to only run Import EDI on 1 thread?  I believe Epicor running Import EDI on 2 threads, may cause the problem as a result of a bug, or competing for resources etc.  We are running on 10.1.500. Thanks.