Have a look at the Europe down load page Alister has posted a link here on the forum and down load the latest firmware and update the nvr assuming your nvr is ml and en version
I don't think we've had any other posts to that effect, and it's also not my experience on that version.
As @marku2 has suggested - try a firmware update or even a refresh of the current version.
If that does not work - for 'configuration funnies' a common fix would be a reset to defaults, annoying though that would be to re-configure from scratch.