Hello,
I mostly solved my issue with:
sudo chmod 777 myfifo
It works but might not be a “clean” way to solve the problem.
Regarding the link Kingosticks provided:
the solution is be to append a line in /etc/sysctl.d/snapcast-unprotect-fifo.conf
however i don’t have this file since i didn’t use snap. I just did:
mkfifo myfifo
Therefore how can i create a fifo.conf file?
Thanks.