My b2evolution Version: 4.1.x

I don't know if my host changed something recently, but I recently upgraded to b2evo 4.1.5 and I notice that when I am logged in as a user and do something such as editing, creating, or deleting a post, I can see the changes immediately on my blog front page.

However, the moment I log out, I see the old content still - even across other browsers/computers.

If I log back in, on any computer, I see the changes. Log back out, and I see the old pages.

If I query the MySQL database directly, I see the most recent data.

I'm not sure what changes in being logged in versus logged out for whatever server side caching my host may be employing.

Any ideas as to what I might be able to do? I saw that XCache is listed in phpinfo(); But why am I not affected by this when logged in?