Use CSipSimple instead of 3CX, it's a much nicer app with far more configuration options.
https://market.android.com/details?id=com.csipsimple
Also, to cut down on latency, you would likely be better off using VoIP.ms' Seattle server instead of Toronto (make sure to change the server on both your DID and SIP client)
https://market.android.com/details?id=com.csipsimple
Also, to cut down on latency, you would likely be better off using VoIP.ms' Seattle server instead of Toronto (make sure to change the server on both your DID and SIP client)