We have a UC540 that is receiving its trunking from a cloud based sip server. They have two trunks on the server, one for voice traffic and one for fax traffic. Inbound this works fine but all outbound traffic goes over the 'voice' trunk. Is it possible to route outbound traffic, from the fxs ports that the fax machines are connected to, onto the 'fax' trunk of the sip server? The sip server only provides one ip address, with unique registration to each trunk.