Hummingbird issues

I have Hummingbird installed on a multisite set-up with domain mapping for other blogs. It only seems to be working on the main blog and not the other blogs in the network.

https://developers.google.com/speed/pagespeed/insights/?url=http%3A%2F%2Fwww.grandviewbarbell.com%2F&tab=mobile

This for example shows gzip is not enabled.