[Hummingbird] Cache break my site

I optimize my website with hummingbird everything is fine.

But one or two days after when I visit again the website certain page doesn't have their css loaded.

So the layout is broke, I refresh my chrome cache but nothing happened.

The only way to resolve this is to clear the cache of hummingbird.

After that the page looks as usual, perfect and the website .

Have you ever experienced this problem ?

Thanks for your feedback and help.