All discussions now marked as viewed

For some reason every single discussion in the forum has now been marked as viewed for my account. This is annoying as I don't read that many, but it is much easier to keep track of the ones I do if they are highlighted when there is a new post. Now every single discussion is being highlighted as having new posts including the ones I have no interest in reading and have never read before.

Is anyone else having the same issue?

Is there some way to re-set this and mark all discussions as un-viewed so I can then just view the ones I normally do again and then continue to just have these ones highlighted?