No audio asterisk behind pfsebse

Hi all members.
i have 2 iphones with zoiper registered via 3G to asterisk (IP 148.XXX.XXX.XXX)
asterisk is behind NAT (asterisk ip is, external IP is 148.XXX.XXX.XXX)
router is fpsense (all configurations are ok)
situation1 - during call between zoiper accounts i have connected call, during 6 sec and then drop autmatically, and within this period there is no audio from any side.
situation 2 -during call from one zoiper account to internal softphone (IP address is
i have sound play in Iphone side and have no Voice in internal softphone side.

@armfranc did you opened the right ports for sip and rtp on the NAT and also on asterisk server ?

signaling 5060-5062 rtp 10000 - 20000

@armfranc ok it looks good but try to open from 8000-20000 since in some cases it had results in some type of softphones that are registered to asterisk server behindd NAT and through vpn connections…