If you're having problems with SIP and calls cutting off after 15 mins, it could be a problem with firewall configuration.
To fix it, check the following:
- Consistent NAT is enabled.
- Single Sign On Authentication Packet is turned off or disabled.
- NAT Refresh Timer is greater than 120 seconds - it may also be called NAT Timeout or UDP Inactivity Timer.
- SIP ALG is disabled - it may also be called SIP Transformation.
If this doesn't work, then contact us.