I found the setting that I needed to change in the template:
Original Code from GenericSIPTrunk.pv.xml:
<!-- Gateway / Provider Outbound Parameters -->
<field name="ParameterOut" custom="" parameter="RequestLineURIUser">$CalledNum</field>
<field name="ParameterOut" custom=""...
We're using Spectrum SIP as that's what our client has for their SIP Provider and does not want to change.
We're using current build of v20.
Spectrum refuses to help with creating a template as their VoIP engineers don't help create templates for phone system PBX per the tech I spoke with...