Unfortunatly, Most Carrier's these days, just say " Here it is " and leave the equipment manufacture's hang out dry, It is one of those settimgs that has to be messed with, it may take several trys to get it working, If Your installer can get ESI on the phone and into the system, they can " see " what is going on and maybe able to make a recomdation as to what Value needs to be in that field, Good Luck !

I can see the light at the end of the tunnel..

Retirement 2019 ( It has happened )