Members Complain of Having to Login Every Few Minutes
 

I've had three members tell me that they've been required to login more frequently in the past hour, which leads me to believe that it's a problem on my end. My cookie and HTTP header options seem to be in order, so I'm not sure what could be causing this error.

Is there any setting that I need to check to ensure that the cookies are working and staying in place on the user-end?