Do I need to buy a Serato DJ Pro Expansion Pack to use DVS control with the DJM-S5?

The DJM-S5 gives you free use of Serato DJ Pro and Serato DVS.
To use certain additional features in Serato DJ Pro (such as Pitch 'n Time DJ), you'll need to buy the relevant Serato DJ Pro Expansion Pack(s).

For details, visit the Serato website [serato.com].