Hi!
I was having the same problem.
I solved by setting the parameters for A604800:
expires {
enableExpires 1
expiresByType image/=A604800,text/css=A604800,application/x-javascript=A604800,application/javascript=A604800,font/=A604800,application/x-font-ttf=A604800
}
I found that we can configure these parameters also in:
Sites> Configuration> LS-Cache
Ps. I had to enter the OLS panel and restart the service to have 100% effect.
Hope this helps!