Samsung i700 - requires hard reset after sleep mode

[ranumm]

I've had my i700 for close to two years now, with no problems until last week. Basically, if the unit goes into sleep mode, I have to press the reset button on the back to get it to reboot (is that considered a hard reset?).

I've installed nothing new in some time, and I've not dropped it or done anything that could have damaged the unit as far as I am aware of anyway.

I've tried just about everything I can think of all the way to a "factory reset" with no luck.

Has anyone expreienced anything like this? Any ideas on what could have caused this, or what I might do to solve it?

Thanks in advance!