I'd try looking at the manual but I can't find it online. Does yours have any diagnostic tips like beep codes?

Otherwise maybe you could try hooking it up to a program card if you have/can find one and update it's firmware, but it may be a bit difficult to find the updates.

I'd also try resoldering as a last resort.

you can try posting in this thread below. It's been inactive for a while but someone might have a better answer there too.

http://www.rctech.net/forum/radio-el...er-rc-804.html