I have SPA 1001 with firmware 3.1.17SE. SPA is behind a NAT. This NAT is router Fritz 7170. On Fritz i configure voxalot acount
xxx@voxalot.com and on SPA i configure
yyy@voxalot.com acount. When i call from fritz to SPA is Ok. When i call from SPA to fritz my connection stoped after 50 sec.
On NAT i forwarded needed ports 5070 (registration) and RCP ports (voice)