You use the Control Panel button in the audio options. It should open the program that your hardware device uses for latency, for PreSonus Audiobox the hardware the program is Universal Control, you might still have to download and install it. If you want to you can open that program on it's own and change settings without opening Studio One instead of through audio settings 'Control Panel' button. Sometimes the settings vanish in Universal Control (I'm on Win10) but rebooting solves it for me.