Stinky Shoes!

So I've have this problem, and I've had it before, but I just figured it was because they were a cheap pair of ballet flats and that they were just old. I ended up throwing them away partially because my feet grew and because they were just so darn stinky!! Since then I have purchased some $50 ballet flats from Nordstrom and I am finding that I have the same problem!
So this time I decided I'd do something about it. I have searched kinda everywhere and have found the following websites the most helpful :) http://www.getsmellout.com/how-to-get-smell-out-of-ballet-flats/
http://www.howtocleanstuff.net/how-to-clean-ballet-flats/
Personally I haven't tried any of them yet, but I'll let you know ;) Also if you've had this problem and you know of a good solution COMMENT! Please & Thank you!