An interesting bug in Premiere Pro CS6.
It took me a while to work out what the common factor was, but it now seems to be the RGB Color Corrector effect.
When the current tine indicator is on a clip using this effect, the Reference window will not update.
And not only doesn't it update the data on the graph, but if you change the type of scope (Display Mode) (e.g. from RGB Parade to Vectorscope), that also doesn't change until you move the CTI to view a clip without the RGB Color Corrector effect on.
I have tested this with both Red R3D files as the source and image sequences. Same thing in both cases.
Extra info:
OS is Windows 7-64 bit
