Yesterday my MacBook Pro (mid-2010 15") crashed 3 times. The first, the screen went black suddenly and I was unable to wake from sleep. The second time the screen froze and then turned off. The third, I closed the lid which caused an ongoing issue with the speakers making a crackle/pop noise and I lost all power (the sleep light and fans shut down). Last week the same issue happened twice in a single day, often within 10 minutes or so. I reset the NVRAM and that fixed it perhaps, or it just didn't occur anymore. To confuse you further, I've recently replaced the keyboard myself by removing all the components and unscrewing it from the top case. When I rebooted I couldn't change my brightness or wake from sleep the first time, but it resolved itself on restart. I suspect something is up with the motherboard. I did a memtest and the RAM appears to be fine. I don't think they are kernel panics since I didn't receive an error report on restart - just that I had abruptly restarted. Any ideas?