While playing, pressing SHIFT + SYNC sets the Deck as the Tempo Master. The Deck's tempo
becomes the tempo reference for all other synced Decks and FX. S5's display shows 
MASTER in
the Deck header of the Master Deck.
The 
SYNC button takes on different states to provide visual feedback:
▪ If the 
Deck is BPM-synced and in phase with the Tempo Master, the button is bright green.
▪ If the 
Deck is BPM-synced but out of phase  with the Tempo Master, the button is  bright
red.
▪ If the Deck is not in sync, the button is dim green.
If a focused Deck gets out of phase, pressing the SYNC button twice let snap back the Deck
into sync with the Tempo Master.
SHIFT Button
The 
SHIFT button is a modifier for other control elements on the S5. It allows you to access
secondary functions. When the Shift button is pressed it lits white brightly.
SHIFT Button
You  will  find  examples  of  using  the 
SHIFT  button  to  access  secondary  functions  throughout
this document.
4.2.7 FLUX Button
 
The S5's 
FLUX button enables Flux Mode for the focused Deck.
FLUX Button
Hardware Reference
The Deck
 
TRAKTOR KONTROL S5 - Manual - 162