Thanks for the update. May I request you to PM me the contact and pricing details where you got your wxc 50 please.Yes, i use the fixed line out, which, IIRC, should be 2V (i seem to recall reading that somewhere). If so, you are most likely using the preamp as an attenuator anyway.
And this 48kHZ resampling (of analog inputs, presumably) - dont have any, so cant comment on it but i do wonder about the effect of repeated A/D and D/A conversions on sound quality.