hello I have the following error running fcdp-tetra_demod.py ./170913/src/demod/python/ fcdp-tetra_demod.py -D hw:1 -o /dev/stdout | ./170913/src/float_to_bits /dev/stdin /dev/stdout | ./170913/src/tetra-rx /dev/stdin Traceback (most recent call last): File "./170913/src/demod/python/fcdp-tetra_demod.py", line 5, in <module> from gnuradio import gr, gru, audio, eng_notation, blks2, optfir ImportError: cannot import name blks2 In Gnuradio 3.7 Block blk2 has been replaced by digital - if the block replaced then the following error occured : then optfir can't be opened --> optfir is reference to optfir.py or optfir.pyc ? If I remove optfir , I have error with sound card access and this : in line 83 tb = my_top_block(options)is also with erreur --