I have an S3 and Traktor Pro 4. I recently bought the S4 from a vendor, License transferred the whole nine. When I disconnect the S3 and connect the S4, Launch the TP4, the S$ does not respond. When going into settings the Control Manager only shows S3. I have downloaded/installed the Windows drivers for the S4 and downloaded the latest Controller Editor/Installed. Reboot the PC and still the S4 is not recognized by the software. Support is impossible to contact.