In the Bria app go to accounts and tap the "+" button.
Select SIP from the "User-defined Generic Accounts" heading.
This will bring up a screen that says "New SIP Account".
Account Name: WhiteSky PBX
User Details
Display As: <YOUR NAME>
Username: <YOUR EXTENSION>
Password: <EXTENSION PASSWORD>
Domain: <PBX DOMAIN NAME e.g. pbxXXXX.voice.wtsky.net>
Voice Mail
VM Number: *97
Navigate to Account Advanced below "Voice Mail"
Advanced Settings
Account Additional
**Leave these at their defaults
DTMF Type
Send DTMF using: RFC 2833
Media Network Traversal
Suppress STUN Wi-Fi: Off
Suppress STUN Mobile: Off
Use ICE Wi-Fi: Off
Use ICE Mobile: Off
SIP Network Traversal
Global IP WI-FI: Off
Global IP Mobile: Off
Call Dialing
Use Tel Uri: Off
Transport and Security
SIP Transport: TCP
Encrypt Audio: Never
SIP Registration
Incoming Calls: On
Refresh Interval: 600
Keep Alive
WI-FI Interval: 60
Mobile Interval: 15
SIP Miscellaneous
Show Miscellaneous: On
Single Register: Off
Passive Session Timer: On
Connection Reuse: On
Enable IMS: Off