Q: Top row of letters on keyboard sporadically stop working

This seems to be a tricky problem. It started out that just a few buttons on my macbook air (2011) keyboard weren't working after upgrading to OSX El Capitan, mostly just a couple letters on the top row of letters (qwerty....) but if I pressed them a bunch of times they would start working again. Now it has progressed to the entire top row of letters not working (maybe one or two letters will work if I'm lucky), until magically they all work just fine again. I've tried checking on speech to text, keyboard inputs, mouse keys, etc. None of those settings are on or causing this issue. Restarting doesn't resolve the issue, it just randomly started working, enabling me to type this question. I'm certain it will be an issue again, just not sure how to resolve it. I'm starting to think that completely reinstalling the OS might help. As a side note, I also have an issue with the screen not coming on occasionally if the laptop is closed and I remove the power cable then open the screen. Not sure if it is related, but figured it was worth mentioning. This also happened after upgrading to El Capitan.