Membership Plugin blocking content that is not protected. Users can not login.

Membership site not accessible to all users. We keep getting reports from some of our users that they are unable to login at all. It seems to be on Mac platforms on Firefox and on some Androids. It seems to be the same symptoms as described here https://premium.wpmudev.org/forums/topic/help-membership-site-not-accessible
Basically our users try to get to the login page are redirected to the 'members only' page as if it is protected content. I can not reproduce this on my windows PCs but enough people including our CEO are seeing it that it is a major issue. The login and sign up pages should be availble to everyone. If this is a cookie issue we need a workaround that is transparent to the users so they do not have to do anything but a membership site that our users can not login to is useless to us. Our site is at http://members.planetwaves.net
We are seeing this On Firefox 28 OS 10.7.8

Other is older OSX running Firefox 29. Same issue on both.

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Is working for now on OS 10.7.5, Firefox 29.

We are on WP 3.8 and membership 3.5.1.3 WPMU DEV Dashboard 3.4.4
It is crucial to our business that we get this fixed ASAP as it is effecting our credibility. Please email me at morvran@gmail.com with any info on this bug ASAP.