Some more specifics will help.  What receiver? Did you change any of the servos?  Switches?  Throttle linkage? I had a servo that was letting interference in to the system through it's electronics.  Changed the servo out and all my problems went away but that was on a 72mHZ sys.

I am running my AeroWorks Extra 260 50cc on a Spektrum DX7 with a Spektrum AR7000 receiver.  There are a number of things about my setup that others would say can cause interference but I've never had the first glitch from it.  This setup has been flying for over a year and a half and not a single thing.  I can't speak for the Futaba 2.4 stuff cause I don't own one but the Spektrum 2.4 is very robust.  Without knowing more about your setup we're just shooting in the dark.