I believe this bug was introduced in Traktor 3.1, but it seems easier to reproduce in 3.2. Version and Setup: Traktor Scratch Pro 184.108.40.206 macOS Mojave 10.14.5 Reproduction Steps: Create two layouts with 4 decks. The deck size doesn't seem to matter. Select the second layout. Restart Traktor. Select the first layout. Observed Results: Deck C&D are no longer visible, even though the first layout is still set to 4 decks. Expected Results: Deck C&D should stay visible.