System and method for monitoring and modifying a playlist of viewable audio and/or video selections at one or more selected times to account for the effects of restrictions on the times, and number of times, a selection is viewed in an internet-based viewing system. The system implements, and monitors compliance with, the performance complement requirements and other copyright restrictions. A selection can be viewed in association with one or more selected advertisements, with limited restrictions or no restrictions on viewing times. Priority advertisements, related to the date and/or to the time of day and/or to payment amount, are given preference. A license, paid for to view a selection, may have unlimited duration or may be limited in time.