I am also seeing a problem in some cases where the port 30003 output to Planeplotter is showing an incorrect heading.
Just seen a BAW 777 on heading 333 in RB appearing on PP with a heading of 27, which happens to be 360-333 degrees.
Also watching a Virgin A340 with a heading of 333 but PP is showing 12, that looks like either no heading has been sent on port 30003 for some time or it might be because the heading hasn't changed. No, heading now 324 in RB My Flights but PP is still showing heading 12.
Perhaps worth checking if some parameters don't get passed to port 30003 all the time, I do notice that SBS-1 Meter is always showing a lower message count than RB does.
Note to Airnav - please ignore, it was the PP settings that were incorrect.