Thank you for asking this question in the support community. ADTRAN does offer Out-of-Warranty Repairs. If you would like to send the unit in for out of warranty repair you can do so by following the instructions on the following page:
Fees and Turnaround Time
Out-of-Warranty repairs will be charged a $75.00 service fee for the evaluation and handling of the unit. If the unit is repaired, an additional charge in the amount of 10% of the unit's suggested retail price will be added to the repair cost. Please allow the following minimum amount of turnaround time, in good faith, for repaired items.
Out-of-Warranty - 60 days
Please, let me know if you have any additional questions. I will be happy to help in any way I can.