Re: packets not being decoded in gnuradio 3.6 but was decoded in 3.4 and 3.5

Hello all,
I have figured out that the code gets stuck at line 275 of the code
attached thus;
msg = self.rcvd_pktq.delete_head()
Can anyone tell me which module is implementing the received message
queue and any ideas on why it will be empty apart from received
frequency not aligned to transmit frequency?