I think that is because of the VFR map, looking at your Coherent spikes, I am thinking that is the cause. You can try to close the VFR map, not only that but to remove it as well from the tool bar. I had the same exact issue that was driving me nuts since the patch and turns out the VFR map is the cause and needed to be even removed from the tool bar.
See it here in action:
I have also sent a zendesk, this is clearly a bug.