"Interferring" devices are just devices that are observed in the air by access points in the course of scanning channels. There is nothing really do do with those devices, because they are just in the air. They could be connected to an access point in the next building over, or just moving past your space. IMHO, you should not do anything with those devices. As long as your network is fortified, "interferring" devices are merely the "radiation" that is seen by your access point and there is nothing to do with them, really.