how exactly are you 'feed[ing] the outputs of the individual buses into the new bus' ?
you must know by now that connecting via jack-connections is a no go situation (unless you insert a jack client in between, just like a stub).
the way to go is probably via aux-sends from audio tracks to output buses. however you must also beware of yet another no go situation like the one briefly discussed here
how exactly are you 'feed[ing] the outputs of the individual buses into the new bus' ?
you must know by now that connecting via jack-connections is a no go situation (unless you insert a jack client in between, just like a stub).
the way to go is probably via aux-sends from audio tracks to output buses. however you must also beware of yet another no go situation like the one briefly discussed here
hth.
cheers