Hi. I wanted to tell you that I made it. It took me a long time to discover a solution that was in front of my eyes from the beginning. In order for AVLinux to be able to select the firewire driver from jack, it is necessary to completely disable ALSA.
I want to tell you that Presonus not only IS COMPATIBLE with Linux, but it never worked better. ZERO LATENCE: I can set the buffer to 64 and it doesn't even immutate.
I'm too happy.
For those who want to make a Presonus FIREWIRE work, to the maximum of its quality and with the minimum latency, I transcribe the solution:
Create a text file in /etc/modprobe.d/ called 'snd_dice.conf' containing only the text 'blacklist snd_dice'.
Run 'depmod -ae' as root.
Recreate your initrd with 'update-initramfs -u'
With the 'snd_dice' ALSA modules disabled you can now use the older FFado drivers, to do this select the 'firewire' driver in Qjackctl as detailed earlier in this sectio
(on page 84).