Signing in on one device signs me out on all others

[Square Wheels]

I have a password protected forum.  It seems if I sign in on one device, I am signed out of that forum for all other devices.  I am not signed out of the site, just the individual forum.

Is this expected behaviour?

[Square Wheels]

Anyone?

I was just on my site this morning, and posts from the password protected section came up i my stream.  Now, and hour later I need to log in?  Again, not to the site, just that forum.