I recently purchased a M-Audio KeyStudio 49-Note Keyboard Controller to work with my Mac. Everything worked fine (as I would expect), but I also fancied getting to work on my Ubuntu installation. After a bit of trial and error I finally have it working 
My M-Audio KeyStudio Keyboard
Step 1
Open a terminal and enter the following:
sudo apt-get install jack jackd qsynth qjackCtl
Step 2
Open Qsynth. Click Setup -> Soundfonts -> Open
Select /usr/share/sounds/sf2/FluidR3_GM.sf2
You will then be prompted to restart the engine. ClickYes.
Step 3
Plug in your USB keyboard
Step 4
Open QjackCtl, click on Connect
Step 5
Select ALSA tab. Drag KeyStudio into FLUID Synth
Close the popup window afterwards
Step 6
Click Start
Step 7
Play music
Notes
While writing this HOWTO I came across this blog post which covers the same topic, but in Italian
cieslak has written this fantastic blog post about why my simple, but functional HOWTO works. Thanks for the link back
Check out Pianoteq if you’re looking for some good piano samples (not really samples since they’re calculated in real time). It is available for Windows, Mac & Linux
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What if you can’t see the MIDI keyboard in qjackCtl?
I could see my keyboard as a USB device, with lsusb.
But it didn’t show up in amidi -l
Nice, no error =) and the qsymth seems to respond by the green light blinking when im playing the midi.
But no sound… do you know any good sound settings that works for you in jack or qsynth?
I was able to fix it by changing audio settings. Thanks Iam really thankfull for this how-to
thx again u saved my day !