We are using MemecacheD for all caching except for Objects where we are using APC. Running the most recent version of W3 Total Cache.
We use Rackspace for our CDN network. I've tried changing the minify cache options, but to no avail. On the CDN tab the Host minified CSS and JS files is grayed out.
I run a few different WP sites and it is happening on all of them.