I feel a little stupid because I can´t really make the Vocoder2 make any sound. I had read the manual several times, and tried anything, but I cant make any signal appears in the "out" vumeter.
Now that you say that, I think that it might be an installation error, because several warning messages appears when SFP starts. I had installed several times, formating and making a new clean install of the OS and always appears diferent warning messages. ALmost them say that one or other effect isnt correctly installed...
Hmm, I would say obtain a copy of SFP 3.1a (not just 3.1) and reinstall. You shouldn't get any errors when SFP loads or your install has issues that a reinstall will likely fix.