Well,… There is one thing you can to but it is potentially VERY DANGEROUS, and it also may help a lot or not at all.
There is a file “/etc/default/grub”, and in that file there should be this line:
Now you need to edit it - in a text editor, as root - and add the word “threadirqs” so it should look like this:
Save the changes and reboot.
Be VERY CAREFUL not to misspell it and not to change anything else because errors in that file may cause your system not to boot at all. The best thing to do is to make a backup copy of that file before you edit anything, so in case something goes wrong you can boot with rescue CD and reverse edited file to its original.
Alternatively you can look for realtime or lowlatency kernels in your distribution’s repository.
I hope you have JACK installed. You don’t actually need it to run Ardour, but in the process of installation, JACK creates a file /etc/security/limits.d/audio.conf (check if it is there) which is necessary for audio to have realtime priority.
If you have JACK installed and still missing /etc/security/limits.d/audio.conf , just run this command:
“sudo dpkg-reconfigure -p high jackd”
and when asked, confirm that you want realtime audio.
Some distributions require few extra steps for the audio to work.
I hope some of that work for you.