I was always impressed with the amount and quality of audio software in Linux. When it all works, and is driven by someone who knows what they're doing, it's essentially a high-end DAW production environment. If it all worked smoothly, I am sure it could be one of Linux and Fedora showcases. 

I am a musical dilettante, so my attempts have been perhaps haphazard, but I had a mixed luck: I was able to get everything to run, but the setup seemed very brittle. I was not very successful debugging the problems because the audio chain is pretty complex, what with the raw devices, ALSA, PulseAudio and Jackd having overlapping roles, and lots of obsolete and conflicting information on the web. I decided to write to the development list in the hope of starting a technical discussion that would result in either technical and/or configuration fixes, or at least some documentation, that I could perhaps help develop.

I have been using the following programs:

play/aplay      simple .wav players
espeak           speech synthesizer
Qsynth/fluidsynth   .midi players/synthesizers
audacity         sound editor
pianobooster  keyboard play-along teaching tool
Rosegarden w/lilypond music editor
Hydrogen       drum synthesizer
Yoshimi          synthesizer
rakarrack       guitar effect processor

As I said, I was able to use all of them successfully, but I had problems integrating them and keeping them up and running in the long term. I wonder if I am doing something wrong, or are there technical issues that I'm running into, currently on Fedora 25 but also on previous versions.

Obviously, out of the box, simple sound obviously works: I can aplay a .wav file, espeak works, and some of the synthesizers like audacity and hydrogen simply work without any preconditions.
Other audio programs require starting Qsynth first: that seems to be the case for Rosegarden, Yoshimi and pianobooster. What is puzzling is that there seems to be a lot of hidden state: after running Qsynth for a while, the simple sound (aplay, espeak) tend to no longer work: they hang without producing any sound, even though Qsynth is no longer running. I tried stracing them, but they just go into nanosleep() busy loops on internal file descriptors, so it's not clear what exactly they're blocking on. I ran into one glitch where qsynth somehow inserted a .wav file as a soundfont in the configuration file, which prevented it from working subsequently (I had to delete the ~/.config/rncbc.org/Qsynth.conf file).

I am planning to log some bugzilla reports, but I am not sure against what subsystems: is it ALSA, or PulseAudio, or Gnome/pavucontrol, or Qsynth. Specifically, I'd like to address the following issues:

- simple sound (aplay, espeak) failing after running fancy synthesized sound apps (Qsynth): I'd need guidance what to test to find the hidden state that causes that.

- fancy sound apps (Rosegarden/pianobooster) silently failing without the synthesizer (Qsynth) running first. I'd like to discuss what could be done to at least produce some error messages directing users to set up synthesizers first, or maybe to automatically start the required synthesizers.