if you were able to set utilization to a given percentage, this suggests to me that they might have VSE 8.7 under patch 3. If so, then system utilization accroding to the manual is performed by taking CPU and IO samples for the first 30 seconds of ODS duration. That determines the usage level for the remaining duration of the ODS. As a result it might mean problems with dual core CPU usage.
From Patch 3, the utilization logic has changed and you can see no longer percentages rather these notches: Below Normal, Normal and Above Normal. This also takes CPU number into consideration and uses Windows Priority control.
I hope I could help.