Good news! I actually made an error when installing Source Unpack. I redid it correctly this time and the problem is GONE! Thanks all!

aaaaand can confirm that source unpack doesnt help either. I too need a solution for this because the freezing is verrrry annoying.

i've tried everything here too: http://steamcommunity.com/app/220/discussions/0/846958223077274345/

EDIT: I made an error when installing Source Unpack. I redid it correctly and it solved the problem!

Can confirm "better computer" doesn't solve the issue.