If you have a firewall, our services may not be allowed.

• Configure the required firewall rules



One of your network devices (firewall and/or router) has an active SIP ALG. SIP ALG stands for Application Layer Gateway. It inspects VoIP traffic and can modify SIP packets.

• Disable the SIP ALG or the configuration of your VoIP devices to use TLS (if supported).



You have more than one internet connection.

• Your VoIP device/client must send the voice (RTP) over the same internet connection as the signaling (SIP).



You have enabled sRTP (Encrypted Voice) on your VoIP device/client.

• Both sides (VoIP device/client and SIP line) must be configured for sRTP.



Your telephone receiver or microphone is muted.

The volume of your speaker is low or muted.

• Check your VoIP device/client.