(a) A franchising authority (or the Commission, pursuant to § 76.945 ) may order a cable operator to refund to subscribers that portion of previously paid rates determined to be in excess of the permitted tier charge or above the actual cost of equipment, unless the operator has submitted a cost-of-service showing which justifies the rate charged as reasonable. An operator's liability for refunds shall be based on the difference between the old bundled rates and the sum of the new unbundled program service charge(s) and the new unbundled equipment charge(s). Where an operator was charging separately for program services and equipment but the rates were not in compliance with the Commission's rules, the operator's refund liability shall be based on the difference between the sum of the old charges and the sum of the new, unbundled program service and equipment charges. Before ordering a cable operator to refund previously paid rates to subscribers, a franchising authority (or the Commission) must give the operator notice and opportunity to comment.(b) An operator's liability for refunds in limited to a one-year period, except that an operator that fails to comply with a valid rate order issued by a franchising authority or the Commission shall be liable for refunds commencing from the effective date of such order until such time as it complies with such order.(c) The refund period shall run as follows: (1) From the date the operator implements a prospective rate reduction back in time to September 1, 1993, or one year, whichever is shorter.(2) From the date a franchising authority issues an accounting order pursuant to § 76.933(c) , to the date a prospective rate reduction is issued, then back in time from the date of the accounting order to the effective date of the rules; however, the total refund period shall not exceed one year from the date of the accounting order.(3) Refund liability shall be calculated on the reasonableness of the rates as determined by the rules in effect during the period under review by the franchising authority or the Commission.(d) The cable operator, in its discretion, may implement a refund in the following manner: (1) By returning overcharges to those subscribers who actually paid the overcharges, either through direct payment or as a specifically identified credit to those subscribers' bills; or(2) By means of a prospective percentage reduction in the rates for the basic service tier or associated equipment to cover the cumulative overcharge. This shall be reflected as a specifically identified, one-time credit on prospective bills to the class of subscribers that currently subscribe to the cable system.(e) Refunds shall include interest computed at applicable rates published by the Internal Revenue Service for tax refunds and additional tax payments.(f) Once an operator has implemented a rate refund to subscribers in accordance with a refund order by the franchising authority (or the Commission, pursuant to paragraph (a) of this section), the franchising authority must return to the cable operator an amount equal to that portion of the franchise fee that was paid on the total amount of the refund to subscribers. The franchising authority must promptly return the franchise fee overcharge either in an immediate lump sum payment, or the cable operator may deduct it from the cable system's future franchise fee payments. The franchising authority has the discretion to determine a reasonable repayment period, but interest shall accrue on any outstanding portion of the franchise fee starting on the date the operator has completed implementation of the refund order. In determining the amount of the refund, the franchise fee overcharge should be offset against franchise fees the operator holds on behalf of the franchising authority for lump sum payment. The interest rate on any refund owed to the operator presumptively shall be 11.25%.58 FR 29753, May 21, 1993, as amended at 58 FR 46736, Sept. 2, 1993; 59 FR 17974, Apr. 15, 1994; 60 FR 52120, Oct. 5, 1995