ti snow input : no sound

[limlo]

hi Guys,
i'm trying to send some audio through the snow but nothing is coming out .
os 3.3.4 , virus control, logic 8.02 ,rme 9652.
i plugged a synth into input R/mono i choosed a preset (clean input to be sure) , i've checked the fx1 page and chosed static mode so envelopes aren't the prob , tried usb out and analog out , checked the filters ... no sound .
i'm not using the snow as soundcard and all the editing is done through VC , i've checked the settings in the config menu dierctly in the snow , everything is set as supposed ; it's the first time i try to use this feature and i've tried all presets , no luck ...
what am i missing?