I’m experiencing a problem with Vegas Pro when working on 4K footage. The external preview (on the second screen) doesn't display correctly—it appears partially on the main screen while the other half of the preview is black. This issue only happens with 4K projects. I tested another project with Full HD footage, and the external preview works perfectly.
I've already checked all the display settings in both Windows and Vegas Pro, and everything seems configured correctly. However, I also noticed another possible issue: the Windows desktop on both screens is not fully filling the display—it has black borders around it. I’m not sure if this is related to the problem in Vegas Pro.
I’ve attached screenshots for reference. Does anyone know what might be causing this or how to fix it?