My guys is about 7 months old and has completely lost interest too. Have you started feeding him something else? I started feeding mine Turks and supers in addition to the crix but now I am back to crix until my Turk colony gets started and he refuses to eat the crix. The Turks and Worms he'll eat. I imagine Crix are not the best tasting feeder out there, of course I am not willing to take on that experiment. LOL.
Have you tried switching feeders?