Sounds to me like you need to set the Default Route
Quality on that port to a low value and then add
sensible quality values for the routes you do need:
In /etc/ax25/nrbroadcast make the 3rd parameter of
the appropriate line 10 (or lower). Then in your
startup files add a line:
/usr/sbin/nrparms -routes <port> <callsign> + <quality>
ie:
/usr/sbin/nrparms -routes 2m GB7xxx-5 + 50
-- Stewart G0LGS