On System Tab, set Primary NTP to: time.nist.gov
On SIP Tab, set STUN enable to YES and set STUN Server to: stun.sip.us
On Regional Tab,
Ring Waveform: Sinusoid
Ring Voltage: 95
CPC DELAY = .2
CPC DURATION = .6
Time Zone: EST= GMT-05:00, CST=GMT-06:00, MST=GMT-07:00, PST=GMT-08:00
Daylight Saving Time Rule: start=3/8/7/2:0:0;end=11/1/7/2:0:0;save=1
On Line 1 make sure SIP Remote Party-ID is YES
also make sure NAT Mapping Enable is YES and NAT Keep Alive Enable is YES
On Line 1 under Proxy and Registration:
Proxy: gw.sip.us
Use DNS SRV: YES
DNS SRV Autoprefix: YES
On Line 1 under Subscriber Information:
Enter USER ID and Password from SIP.US site (User = Trunk # and Password is SIP.US Trunk Password)
On Line 1, USE THIS DIALPLAN: ([49]11|[933]|1xxx[2-9]xxxxxxS0|<:1>[2-9]xxxxxxxxxS0|<011:>x.)
***To ensure that inbound calls work properly, go to the "SIP Trunking" tab, and select "Modify Trunk." Then ensure that "Contact Override" is set to "OFF." You can test inbound calls on a Demo Account, by following the instructions in the red box on the right side of your portal which says "Get a Free Test DID for 4 Hours..."***