Hello Richard,

it looks like chameleon and responsivizer do the same thing, detects devices thus probably can't work together, or at least they trigger a race condition.

I've never tried or worked with Chameleon and i don't know how it work but i guess that it's based on a system plugin like responsivizer.

In this case you can try to change the ordering in the plugins list for the responsivizer template switcher and chameleon to see if something changes.

Greetings,

John