If the plaintiff is not the original creditor and does not have said "voluminous" records, don't they fail to meet the burden of proof?

I am a lawyer in CT and practice in this area of the law.  the plaintiff does not need to be the original creditor.  as long it can prove that it is the current holder of the note or payee pursuant to a contract that you are obligated to pay, it may enforce its payment rights.  usually, companies purchase debts from other companies or companies assign their right to payment from you to another company that then stands in their shoes.  Therefore, you may defeat summary judgment is you can prove that there is a dispute of fact as to whether they are the proper creditor- i.e. what documents did the plaintiff provide that show they were assigned or purchased the debt you owe.