Uniden uip200 not registering correctly

I don’t know if anyone has come across this problem with the uniden uip200 with astersik ver 1.2.3 where the unidens will show ‘unreachable’ in the ‘sip show peers’. This happens when in the sip.conf you sent the qualify=yes value. When this is set you can dial out to any other phone but you cant recieve any call. However if I set the qualify=no it works but shows as unmonitored in the ‘sip show peers’ command. It can then call and recieve calls. Any help greatly appreciated.