Invoice Validation Performance in 12.2

Has anyone figured out how to get better performance with the Invoice Validation process in Oracle 12.2?  What used to take seconds to validate, now takes minutes.  We've tried modifying the Profile setting and the Concurrent Job parameter as instructed by the items on the Knowledge Center but have not found any combination that works.

So do not process an enormous amount of invoices but some batches may have up to 80 invoices which used to take seconds to validate from the Invoice Batch Workbench.

Thanks for any assistance,

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