Trunk registration

FreePBX Installation / Upgrade
1

When i use netgear hub i can obtain two trunk registrations and
dont have any registration,inbound,outbound,or audio issues. The hub is a dinosaur and very noisy, so i purchased a Linksys 4 port router and have just have one problem. The issue with the linksys is i usually only get one trunk registration but when the second trunk registers no calls can be placed at all, phone reads url call disabled. Could this be double nat problem, both the router and modem have nat enabled.
I can unplug the router for 10 seconds and drop one trunk registration then phone works fine untill i hit save in the router with out even making a change then both trunks register and all calls fail

Filter Multicast:Enabled Disabled	 
Filter Internet NATRedirection:EnabledDisabled 	 
Filter IDENT(port 113)
    IPSec Passthrough:	Enabled 	
PPPoE Passthrough:	Enabled 		
PPTP Passthrough:	Enabled 
    MTU    disabled
    upnp   Enabled
    I have not set up any port forwarding because its been working with out
2

Its not saving a file. Its putting it in the database and when you reload it writes out the network configs in ifcfg-eth0

3

thanks Toney, that makes sense.
not to confuse others but the topic has slightly changed

4

I’m also getting this error

SIP/fpbx-1-ac07bd49-00000004", "SV_DIALSTATUS=CHANUNAVAIL
app_dial.c: Unable to create channel of type ‘SIP’ (cause 20 - Subscriber absent)nt)