On my initial setup of GP I was using a Radial Engineering AO that used the Windows Media driver and I was using a DROK USB Volume Control Knob for my master volume knob (big knob Velcoro’d to my controller for super fat volume adjustments). I’ve since upgrade my AO to a Scarlett 4i4 but the ASIO driver doesn’t support the DROK. Is there a 3rd-party driver to allow a generic HID-class USB device with GP?
From my understanding, the knob controls Windows system volume, which is why it was working when you were using the Windows Audio driver for your audio applications. It wont have any effect when you use ASIO (not just for Scarlett, but any ASIO device).
Have you tried contacting the manufacturer about seeing if there’s some mod that can be applied for this? I’m not finding any search results for such a thing.