I dont recall Futaba actually recalling and radios. They did put out a safety advisory when the 2.4's came out because some pilots were not installing the receivers correctly causing a loss of signal.
The antenna leads must be at 90˚from each other.
I bought the 6EX 2.4 when it came out several years ago and it has been working perfectly ever since... I've since purchased a 7C which is also a great radio...