Hmmm

That is very strange that both channels failled.
What radio is it? I would look there first.

Maybe you have some weird setting on it or something.

Maybe it has a glitch in it
For example:
I was told by hitec that my optic 6 had a glitch. The channels would lock up and you would have to turn the radio off and on if a certian setting was set like at %50 and you moved the stick in a certian way.