A method for communication includes providing a first transceiver configured to communicate with a second transceiver over a bi-directional link having a first aggregation of frequencies that are assigned to carry first communication traffic in a first link direction from the first transceiver to the second transceiver and a second aggregation of frequencies that are assigned to carry second communication traffic in a second link direction from the second transceiver to the first transceiver. Communication feedback is transmitted from the first transceiver to the second transceiver communication feedback at an adaptive feedback rate. The feedback rate is determined so as to achieve a desired balance between the information carrying capacities of the first and second aggregations. An information carrying capacity of the second aggregation is controlled responsively to the communication feedback.