How did you prevent the ALSA driver from loading? The kernel will load the ALSA drivers automatically, so unless you understand the process for preventing automatic loading of drivers, or you manually unloaded the kernel driver, you did not actually try without ALSA. That is why I have recommended multiple times that you try using just the ALSA drivers, forget about FFADO for now.
As Paul wrote above
I tried to warn you as well, but apparently you did not realize the implication I was pointing out of having firewire support in the ALSA drivers:
I think you have a learning curve ahead of you if you want to work against the automatically loaded kernel drivers, which is why the recommendation would be to use the ALSA drivers and not FFADO if the built in drivers work for you.
That allows you to make setting changes to the Multimix, but has almost nothing to do with setting up Ardour or jackd to use the device.
The jackd audio server is what provides the ability to connect Hydrogen and Ardour (and other audio apps) together. It manages access to the audio device, and allows routing audio and MIDI to and from different applications and the audio hardware. QJackControl (which I assume is what you are calling qjack) is a graphical application which allows you to select settings for jackd with pull down menus and then sends your selected settings to jackd, which is the application which actually runs to perform the audio routing.
QJackCtl web page
JACK audio server web page
I suspect that since things just worked for you in the past you never really needed to concern yourself with what was going on behind the scenes.
So this is my recommendation:
In QJackCtl in the setup page, in the “Driver:” drop down box, pick “alsa” as the driver type, then whatever device name looks like your mixer (will probably be hw:Multimix or something like that).
Set frames per period to 1024, which should have a reasonably good chance of running with no underruns (if this works you can refine that setting later). Use whatever sampling rate you usually use and start it up. If that works then you are good to go, just put “firewire” and “ffado” out of your head, that’s the old way of doing things.
If that does not work with your device, then you have to go against the flow a little bit to get the old way working again.
Open a text editor and create a file named something like no-alsa-fw.conf and put this text in the file:
Save that file, then if you know how to use administrator privileges from your favorite graphical file utility you can move it to /etc/modprobe.d
If you are not sure about how to do that (I think the file utility should just ask for your password when you move it), then you can do this from the terminal shell (in the directory where you saved the file):
sudo mv no-alsa-fw.conf /etc/modprobe.d/
That will add the file you created to modprobe.d directory, which is searched for conf files at boot time to find the list of drivers which should not be loaded automatically. All those drivers which begin with “snd-” are ALSA drivers for firewire devices. If from the command prompt you type
lsmod | grep snd
you will probably see one or more of those drivers loaded.
After moving the file to the modprobe.d directory reboot your computer, and after restarting when you run that same lsmod command you should not see any of those firewire snd drivers loaded. Without the ALSA driver loaded you now use FFADO as you did in the past, by selecting “firewire” in the driver selection box in QJackCtl.