You said you "miss being able to use the 770", does this mean you have used the 770 before and it was doing fine? If that is the case, then I think you can blame the aging OS of the "PDA". Also, it may have been damaged on an occasion you failed to notice.
My cousins in the UK owns a Nokia 770 and never complained about that problem. The only concern I know they have about the 770 is that it's pretty slow connecting to a WiFi and that screen keyboard is relatively slow. The greatest concern they have about the 770, however, is the super low price of the phone just after more than two years of its release when in fact they bought it at more than double the current price. LOL!
Why not try to bring your phone at any Nokia support center? Or perhaps, upgrade it for the new Nokia N800?