Reply to Traktor is not co-operating.

As the title says, every time i open Traktor scratch pro it does not work properly.

My main issue is that deck a will not play and deck b will not stop playing, while decks c and d appear to operate normally. This happens if i open either Traktor scratch duo (the 1st release) or Traktor 2 scratch pro. Both have exactly the same problem (obviously without duo having decks c and d to check).

If anyone has any idea how to solve this it would be much appreciated, i'm completely out of ideas apart from a full removal and re-install.