I'm posting both here and Any Mobile Theme Pro's support.
I have followed the instructions to ensure W3 Total Cache should work with 2 themes (desktop & mobile) with Any Mobile Theme Pro. Instructions for this are here:
http://dnesscarkey.com/any-mobile-theme-switcher-pro/w3-total-cache-setup
But still randomly I will visit the site on desktop and see mobile tehme and vise versa...
This is very scary to me. I just want it to work. I'll pay to make this just work 100% without this ongoing nightmare that I'm losing customers...
What do I need to do to ensure this works 100% of the time? I need to have some form of caching so what is the solution to this ongoing issue?