Membership plugin randomly logging out users?

I have some protected areas on my website. I’ve configured this two ways.

Some pages are entirely protected using URL Groups. I have one “member” group, and a visitor group. I restrict access to the member pages by setting a negative rules on the Visitor access group.

I have a few pages where anyone can access it, but some content on that page is accessible only to members. This content is protected by using the member-level access group short code within the page.

For both of these groups, I am getting reports of people who visit the member areas and are being logged out. These people are logged in and part of the member access level, so they should be accessing the area fine.

It doesn’t seem to be restricted to a certain browser/OS, and I haven’t been able to replicate the problem myself, and it’s not happening to everyone, however, I’m getting enough reports of it happening that I’m convinced there’s an issue somewhere.

Is there something I might have misconfigured to be causing this, or some sort of weird known bug? This only happens when they visit one of the protected areas, I haven’t had a single report of them getting logged out on non-protected pages.

Thanks