..the funny thing is my expensive 4PX has had this issue on more than 1 occasion (where it has trouble binding to a receiver), however I have yet to experience this w/ my cheaper 2PL or 3PV controllers. In fact the same receiver will bind just fine w/ my 2PL and 3PV but not the 4PX (which was a higher end controller). (note, this is even after toggling between the various s-fhss, t-fhss, etc protocols).