Mid-2010 Macbook Pro - Sudden Issues everywhere

Question

Ok, so I've got a Mid-2010 Macbook Pro and just before Christmas all of a sudden issues just popped up everywhere. I'll give you a rundown of what all i've seen and what all I've done since.
So I start getting a message something like
- AppleSecurity - Unauthorized caller ...popping up intermittently. And then,
- Firefox, once you shut the window down you couldn't get open again, and when you quit the app the computer seemed to freeze
- ITunes wouldnt open
- App Store wouldnt open
- Safari would only open some webpages
- Steam worked 10% of the time.
- Powerpoint and Word would crash or not save etc.
- I had to push the button to restart to get the thing working again and from time to time it would freeze or crash shutdown at the grey screen.
- I kept getting small indications that the memory was full.
- Cant shut down or restart without holding the button
So I deleted stuff, generally cleaned up unneeded files etc. ... Same problems. I eventually got so exasperated that I just stuck everything I needed on a flash drive and wiped the user and started a new one.
Same problems but slightly better.... So at this point I go into the Apple Store and go to the Genius bar - The guy wipes runs a check on my hard drive and everything ticks the boxes barring battery which is at 74% roughly. Then he wipes everything off to a factory restart, updates it, then hands it back.
I get it back home and I have issues even setting up the user as if it was a new macbook. I have untick all the set time zone and network stuff to get it to work.
I get it back going and ... still problems... but slightly better. But I cant update flash, steam crashes, sometimes again things dont work. Safari sometimes doesnt open some webpages and I have to restart to get things to get working again.
Also, things seem to be a little better when I'm using the universities internet as opposed to the one in my flat.
SO...! Back into the Apple Store, Genius Bar, he runs a full check on the drive because he seen some I/O errors in the console. AND.. everything passes. He runs a full daignostic and still can't figure it out. He says he seen some weird messages about Steam causing problems in the console but that was it, which I dont think could be the problem because I was getting problems before I even reinstalled it after the factory wipe/reset. The network causing problems maybe?
What do I do people? No-one at the Apple Store can pinpoint whats going on?! I really want to get this fixed because I need this for uni and I can't afford a new one
Please Help!

Answer 1

poikkeus1,
After getting a "properly" functioning LB, the temps are much lower than that, even when beating onit doing live recording. idle 25-30 degrees max, beating it with a "pile of inputs" recording 65-70
The first machine i spent over 4 hours with a senior engineer doing an ARA, it was like someone took a shotgun and blasted the data all over the place.
I switched machines (after 30 days, which would say they knew they had an issue)
Second time temps off the map, and unexplainable "bizzare" behavior. (random)
second time same deal, all over the place.
Now everything seems happy, for months now. (I hope I just did not jinx myself)
It sure seems that would be the place to look, hence you should ask for the flat rate repair.
Best