Hi, With gnuradio 3.6.3 I am using the gr_message_burst_source to generate messages (one message per second) and set the bob and eob correctly. After this block I connect the following blocks to send bpsk modulated messages : packet_to_unpacket_bb, map_bb, chuncks_to_symbol, rrc_filter and the uhd_usrp_sink. However, I get many "U" characters in the screen, and many errors in the reception. I think that one or many blocks of the previous ones do not propagate the tags properly. I appreciate any help to solve this problem/question. Thank you.