lobster.

assuming your not recording multiple synths at the same time...(am i correct ?)..
why not just reserve a input line channel on mtk and feed it from line out of the xenyx ?
or am i missing something re your rig ?

you could also...like many musos used to do use a 'switcher' hooked into one mtk
channel ? for multiple synths etc where your recording one at a time ?

are you recording a large band ? where everyone plays at the same time ?

happiness.

om

my songs....mixed for good earbuds...(fyi..my vocs on all songs..)
https://soundcloud.com/alfsongs
(90 songs created useing bb/rb)
(lots of tips of mine in pg tips forum.)