[Discuss-gnuradio] Warning while running gr-ieee-80211

Ubuntu 16.04

GNURadio and gr-ieee-80211 installed yesterday using pybombs 

I get this warning when I run the wifi_rx.grc

"The total sum of rates (20.000000 MSps on 1 channels) exceeds the maximum capacity of the connection"

And then a lot of overflows. 

I was generating 802.11g using a VSG. My gr-ieee-80211 receiver is not detecting anything. 

I remember I performed the same test in June this year and results were 99% (over the air).

Whats happening wrong ? 

Regards

Sumit