Built-in Keyboard and trackpad become unresponsive randomly

Question

I've been researching a lot on this but no case seems to apply to mine.
Out of nowhere, about once a day, the built-in keyboard and trackpad of my 2010 MacBook Air will stop working. The only thing that works is the power button, which brings up the power dialog in which I can't do anything. I can also do a hard shutdown.
However, if I connect an external mouse and keyboard, they work. With just a restart through them or a hard shutdown, the built-in keyboard and trackpad start working perfectly. This makes me think it's a software issue, and thinking about it, this didn't happen before 10.8.4.
I ended up resetting the PRAM, the SMC, and finally erasing my disk and reinstalling OSX. After that, I have ONLY installed Google Chrome, nothing else, and it's still happening.
I don't live in the U.S, so taking it to Apple is impossible plus the issue is not easily reproduced, not to mention the computer is almost 3 years old.
Any ideas? Thanks!

Answer 1

The next time you have the problem, note the exact time: hour, minute, second.
If you have more than one user account, these instructions must be carried out as an administrator.
Launch the Console application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad. Click Utilities, then Console in the icon grid.
Make sure the title of the Console window is All Messages. If it isn't, select All Messages from the SYSTEM LOG QUERIES menu on the left. If you don't see that menu, select
View ▹ Show Log List
from the menu bar.
Scroll back in the log to the time you noted above. Select any messages timestamped from then until the end of the episode, or until they start to repeat. Copy them to the Clipboard (command-C). Paste into a reply to this message (command-V).
When posting a log extract, be selective. In most cases, a few dozen lines are more than enough.
Please do not indiscriminately dump thousands of lines from the log into this discussion.
Important: Some private information, such as your name, may appear in the log. Anonymize before posting.