Display dim on one monitor when Surface is docked?

[Windows Central Question]

Display dim on one monitor when surface is docked ?

I have a surface pro 3 set up with dual monitors- the cables we use are mini display to DVI. One of the cables is connected to the docking station and the other to the surface. For some reason, the second monitor ( irrespective of whether it's connected to surface or dock) is very dim. I've tried swapping out cables and even connected a brand new monitor and had the same issue. The brightness settings are 100% on Surface as well as monitors. Drivers are up to date. Any ideas on how I can fix this?

Thanks!