The non-compatibility of some receivrs with Futaba transmitters equipped with synthesized frequency modules has been known for some time in other Futaba transmitters.

Again, it is not Futaba's responsibility to ensure that their transmitters operate any receiver the user may desire to use. They can only assure you that their receivers operate correctly with their own transmitters. If a particular piece of non-Futaba equipment is not compatible with Futaba equipment, then it is that maker's job to make it so, if that is their goal, not Futaba's.

One more thing...Futaba cannot guarantee that their equipment is suited for a particular individual's needs or use. If a particular Futaba transmitter does not suit your needs, then it is certainly not the one for you.