Mention that Vulkan drivers are required for DXVK

README.md

@@ -450,7 +450,8 @@ include:
 - If a plugin seems to work fine except for the fact that the GUI never seems to
   update when you interact with it, then try installing
   [DXVK](https://github.com/doitsujin/dxvk). Many recent JUCE-based plugins
-  don't redraw anymore when using WineD3D.
+  don't redraw anymore when using WineD3D. Make sure you also install Vulkan
+  drivers if you don't already have those set up.
 - **Serum** requires you to disable `d2d1.dll` in `winecfg` and to install
   `gdiplus` through `winetricks`. You may also want to disable the tooltips by
   going to the global settings tab, unchecking 'Show help tooltips', and