Filter not working

Hi


This is a list of my MIDI devices:


  28:0    MicroBrute                       MicroBrute MIDI 1
  28:1    MicroBrute                       MicroBrute MIDI 2
  32:0    microSTATION                     microSTATION MIDI 1

I have connected both the microSTATION with the MicroBrute using 
aconnect, so when I play the keyboard, the MicroBrute synth is played:

aconnect 32:0 28:0

And this is the way I'm trying to connect them, so I transpose by +12 
half notes, the input coming from 32:0 to the 28:0, which is the synth 
I'm trying to get sound from (using rmidish):

[0000:00]> dnew 0 "32:0" ro
[0000:00]> dnew 1 "28:0" wo
[0000:00]> inew ms_1_27 {0 1}
[0000:00]> onew mb_1 {1 1}
[0000:00]> fnew ms_mb
[0000:00]> fmap {any ms_1_27} {any mb_1}
[0000:00]> ftransp {any mb_1} 12
[0000:00]> i

But I don't hear any change. The synth plays same octaves, no 
transposition done.

Can anyone let me know what's missing?

Thanks

Nicolas