This has been discussed here in the past. If I recall the trick is to use the wizard to configure the Patton then delete the route that it produces in 3CX and create 4 new routes each with 1 call capacity and with the ports being appropriate eg 5060 for 1st router, 5062 for 2nd route, 5064 for 3rd route, 5066 for 4th route. Then determine in your outbound rules what traffic goes out on which line remembering that you can set 1st, 2nd and 3rd preferences. I ahev this setup at a client but I am not able to connect at the moment to refresh my memory
Dave Phillips