DBMS_SCHEDULER error deadlock

I am running into an issue scheduling jobs via DBMS_SCHEDULER, where I get the errors:

ORA-20001: schedule_job: ORA-04020: deadlock detected while trying to lock object SYS.SCHEDULER$_EVENT_QUEUE, FORMAT_ERROR_BACKTRACE: ORA-06512: at "SYS.DBMS_ISCHED", line 8210

ORA-06512: at "SYS.DBMS_SCHEDULER", line 4353

This happens on two of our databases. However, when I rung the exact same code as SYS, it starts working for all users but eventually will be tossing the above errors again.