Using both I and Q on LFRX

I’m using the LFRX board on a USRP2 under grc version
3.3git-534-ga198e513

I’ve connected a USRP2 source to a scope sink configured for complex
input. The RX-A input maps to the real component of the complex signal.
I had hoped that RX-B would map to the imaginary portion but I’m only
seeing zeros. Is this expected?

-Phil Rutschman