Basic Flowgraph

When running a single channel, I get a nice clean and stable signal. When I run 2 channels I get weird corruption of the data as shown below. In the image below, you can see the noise pedestal of the input filter disappearing periodically. Any injected signal is also corrupted during this time.

I have tried using the gr-bladeRF block, but can not get this to build with GRC3.9. Not sure if this would fix the issue, but I could downgrade Gnuradio if anyone thinks its likely to help.
If anyone has and tips/tricks, or can replicate the issue I would be appreciative?