Had a power outage and one of my VG224 GW will not provide tone any more. I have checked for physical damage, none. Checked continuity from the gateway to the 66 block. Reset the ports and the gateway itself. Still no tone. The only thing that I do notice is that the activity light is not lit on the FXS connection. There are actually two VG224 GW(s) and the first is working just fine. This one will not give any tone, not sure what to do next. Any suggestions?