Inverter problem?

[nmos]

I'm trying to repair an A21p (12" screen) that has intermittant backlight. Sometimes it just turns on like it should but other times it (the backlight) either doesn't come on at all or takes about a minute to come on. If/when it does finally come on it will stay on for as long as I'm using the machine and the brightness/color seem normal. I've also noticed a whine coming from the speakers when plugging in the power with the machine off. One last item is that when the backlight doesn't work, the keyboard light seems stuck on.

Does this really sound like an inverter problem or could there be something else wrong?