I agree JT. I'm not happy about the answer - I'm happy that he followed up with Numark. Now to see what Serato says.
Agreed that if you're not meeting the specs, that's quite possible the cause of the problems. I'm a little more interested in why his machine did work with his buddies Numark with no errors. Even if his machine does not meet specs (which may be the cause of the problems), then why does it work with his buddies controller. Can you take your machine and controller to a Guitar Center / other similar store and try your controller on their machine - their controller on your machine - and test for the same errors? Do you know anyone else with the same controller that you can test with?
In either case, if you don't meet the specs, these companies may not have much help and may lay the blame there because that may be the cause. Example, if you don't meet the specs that Rick writes the software for, he may not be able to help you because it is outside of the realm of what he is supporting. All software and hardware vendors follow this practice. This is not unique to Serato nor to Rick.