I pushed a commit to rr module adding a new parameter that allows enforcing send socket even on a single Route header - see 93739c0b8674a09f8364eac6f28bcc91b167843a .
Testing and providing feedback will be appreciated.
Anyhow, for older versions you can force the socket from config, after loose_route, do something like:
``` $fs = $pr + ":" + $(route_uri{uri.host}) + ":" + $(route_uri{uri.port}); ```