It seems that when my system is in sleep mode for too long it just shuts off and I have to press the power button to turn it back on. This used to never happen but happens to me now every morning. Used to be in the mornings I would open the lid and there was the login screen within a second or two. Now I have to press the power button and when everything loads Chrome complains that it shut down unexpectedly. I haven't been able to determine how long it has to be in sleep mode before it does this. Seems like if it's just a few hours it's not a problem. In Energy Saver preferences the only option checked on the battery tab is "Put hard disks to sleep when possible". I'm not certain if this happens when it's plugged in. Any thoughts on that? I did reset the SMC and the NVRAM for what it's worth.