Blue cast to recordings with R800

[bhelander]

Hoping someone can advise...  mine is an indoor location setup for teaching.  I have the area lit by two soft boxes and am using two R800 cameras - one is for overhead tabletop down shots and the other camera is off to the side to capture me sitting at the table.  Both cameras the white balance was set to custom.  For a while, the colour outcome of both cameras was spot on, but for some reason one of the cameras (the side camera) has started recording with a blue cast.  Cannot figure out what  going on.  
Anyone have any thoughts?
Thanks!

[rs-eos]

Any ambient in the scene that is changing?  Though that would affect both cams.  Yea, no idea outside of the problematic cam geting its white balance setting accidentally changed somehow.