wrong antenna mode

Hi,

I am using a X310 under uhd4.1.0.5, gnuradio 3.8 and rfnoc.
Whenever I use an antenna mode with either usrp sink or source, I get an
error stating: invalid antenna mode: RX/TX

python error is:
return_uhd_swig.usrp_source_sptr_set_antenna(self, ant, chan)

How to solve this?

Thanks in advance,
Maxime DUPONT