MBP with Mountain Lion 10.8.3 loses connection to system SSD at random times and freezes So, out of nowhere my 2009 MacBook (2,66 GHz Core 2 Duo, 8 GByte aftermarket ram) started freezing after 200+ days of uptime (sleep time included of course). I had installed a Crucial CT256M4SSD2 256Gbyte SSD a year and a half ago and were quite happy with system stability.

Now these logs appear quite often before freezing my machine completely:

disk0s2: no such device
disk0s2: media is not present


Here is a photograph of such a log (original, larger sized photo here):



The reason I had to do a photo is, of course, because disk0s2 is my harddrive and at the moment of logging it was apparently gone - so no persistent logs for me.

I tried a diagnose and repair with the Disk Utility, but it found nothing and the problem persisted. Uninstalled a couple of apps, but also to no avail. Any advice on how to proceed with diagnosing the problem would be much appreciated.
A firmware update for that SSD was released early this year: have you updated?  The release notes mention:


  Resolved a power-up timing issue that could result in a drive hang, resulting in an inability to communicate with the host computer. The hang condition would typically occur during power-up or resume from Sleep or Hibernate. Most often, a new power cycle will clear the condition and allow normal operations to continue.


(Personally I'm using a CT128M4SSD2 and have decided not to update unless I encounter issues.)