Hello, > OK, I am not familiar with this device. Is this essentially a soundcard or is > it slightly different in some way? No it isn't a Soundcard, it's a device connected to the serial port to the computer, that convert midi data in sound. The Soundmodul isn't listet in the Alsa Support List, but it's no soundcard. > Weird. Yes, and i can't find any reasons, or midi-data that "reset" the midiport. in my /etc/modules i added only : snd-serial-u16550 port=0x2f8 irq=3 it dosen't matter if i remove this line and do it manually : setserial /dev/ttyS1 uart none modprobe snd-serial-u16550 port=0x2f8 irq=3 in both cases "aconnect -o" show me the port 20:0 for the snd-serial-u16550. aplaymidi -p 20:0 song.mid dosen't play anything ( it seems the soundmodul dosen't get any midi-data, because the midi-data-LED dosen't blink ) a restart makes the LED blinking and i'm able to hear the music. thanks, Marian