I have a 1AP here too; no problems on my end.. however, I went through one already
Casio almost did a recall of the e200 because of this.. but didn't as it wouldve been too expensive.
anyway, its not
what you do to the unit that will destroy the backlight permanently. it can go out at any time (when the light is switched on or off, seems to be a wiring problem), and
will within the first week (or day, if youre a total ppc geek like me), and you will smell that burnt electronics smell that fish mentioned.
however, if you have a 0ap-4ap unit that has been working fine for a week, with no problems (including the it shut down and will never come back on problem.. where that one happens in the first few days as well) then you have one of the few good working devices

,
which is why there was no recall
