Quality of SIP calls behind openvpn

Daveron · Post by **Daveron** » Mon Jul 02, 2018 7:00 am

Hi,
Im using Asterisk pbx hidden behind openvpn server. Endpoints are installed on Android Phones. This configuration is working quite good, but voice quality gets very bad when phone user is driving a car (so we have lot of handovers). Im using 8k codec (speex),

Could some1 give me any clues how could i improve my configuration to get better voice quality?

I already set up:

sndbuf 0
rcvbuf 0

My full config:

local <ipaddress>

port 1194

proto udp

dev tun

ca ca.crt
cert server.crt

dh dh2048.pem

server 10.8.0.0 255.255.255.0

ifconfig-pool-persist ipp.txt

push "route 10.1.0.0 255.255.255.0"

push "redirect-gateway def1 bypass-dhcp"

duplicate-cn

keepalive 10 120

user nobody
group nogroup

persist-key
persist-tun

status openvpn-status.log

verb 3

mssfix 1150
tun-mtu 1200

sndbuf 0
rcvbuf 0
fast-io

Best regards, Konrad