Abstract: The invention relates to a system for multimedia content distribution, the system comprising: an Over The Top streaming server adapted to distribute multimedia contents over an unmanaged network with multiple available levels of quality; a central monitoring unit adapted to receive technical metrics from probes at consumer's devices and to aggregate information relating to perceived quality of each of the distributed contents; an agent adapted to receive the aggregated information and to act on the OTT server whenever a discrepancy is observed between the perceived quality of a given content and a predefined quality class assigned to said content, wherein the agent is adapted to act on the OTT server by modifying the availability of the levels of quality for a plurality of distributed contents.