We are using 3cx v10 sp5 and we use a patton 4114 for two incoming phone lines. Randomly when calls come in on the first line on that patton they show caller id and ring once. Then appear to disconnect before we can pick them up. Then a about 5-10 seconds later they ring again as anonymous caller and it is the same client. This is very random and I don't know where to start troubleshooting this. Any Ideas?