Concluding everything said here, it is unfortunately rather likely, that the sorage medium experiences a hardware fault.
The more random the errors are, the more likely it is a hardware fault. Especially with random file corruptions all over the place, without reason. Usually software related issues like that get resolved at least by a full clean upgrade or reinstallation.
You probably need to replace your current sorage medium with a newer, working one. If you have still warranty on this one available, you should make use of that.
You could try using the badblocks utility, however I am not sure how effective it is for solid state drives.
I just read through the bug thread on launchpad and discovered, that the guy says pretty much the same as I do: