Problems with gr-osmosdr and dual-channel B210 support

I’m getting this startup sequence here:

linux; GNU C++ version 4.8.2; Boost_105400; UHD_003.007.002-85-g5ffc835e

Using Volk machine: ssse3_32_orc
gr-osmosdr v0.1.1-13-g58d95b51 (0.1.2git) gnuradio 3.7.4
built-in source types: file fcd rtl rtl_tcp uhd hackrf bladerf rfspace
– Operating over USB 2.
– Initialize CODEC control…
– Initialize Radio control…
– Performing register loopback test… pass
– Performing register loopback test… pass
– Performing CODEC loopback test… pass
– Performing CODEC loopback test… pass
– Asking for clock rate 15.200000 MHz
– Actually got clock rate 15.200000 MHz
– Performing timer loopback test… pass
– Performing timer loopback test… pass
– Using subdev spec ‘A:A A:B’.

FATAL: output port 1 out of range for gr uhd usrp source(51)

Trying to fill up 2 missing channel(s) with null source(s).
This is being done to prevent the application from crashing
due to gnuradio bug #528.

The device arg that is being used to gr-osmosdr is:

uhd,nchan=2,type=b200,master_clock_rate=15.2e6


Marcus L.
Principal Investigator
Shirleys Bay Radio Astronomy Consortium