Try rebinding your system, BART. I haven't heard of that problem before; especially with Spektrum's products.
2.4GHz is like night and day compared to AM and FM technology. With 2.4GHz you don't have to worry about glitching if the system is bound correctly, you don't have to worry about interference from other radios or even other electronic devices and! you can even still run multiple RCs off of the same transmitter if the transmitter supports that option (you'll just have to buy spare receivers).
If you can afford it and the option is there, go with 2.4GHz. AM and FM work, but 2.4GHz takes a lottt of hassle and worry out of driving.
Cheers,
Kyle.