Last week, I installed Ubuntu Studio 16.04. (Previously, I was on plain Ubuntu 14.04.)
Current state: Audio is working as I want it to, for USB soundcards. The laptop's built-in soundcard is not pumping any audio out.
GOAL: I want all audio traffic to go through JACK, all the time -- JACK launches ALSA. Unfortunately, I can't do without PulseAudio. I want PA *always* to use the JACK source and sink, and *never* to connect independently to a different sound card.
- Initial, OOTB configuration: When I start it, the JACK server takes over the specified audio hardware. PA creates the JACK source and sink, but it does not use them by default.
- I tried to set the source and sink as PA's defaults, but (as I recall) the behavior was inconsistent. Sometimes everything would hook up. Sometimes the source and sink would fail to be created. Sometimes they would be created but not used.
- So I tried to go back to the trick I had been using in my old environment:
- Turn off PA auto-start: add to /etc/pulse/client.conf: autospawn = no and daemon-binary = /bin/true.
- ~/.pulse/default.pa:
Code: Select all
load-module module-native-protocol-unix load-module module-jack-sink channels=2 load-module module-jack-source channels=2 load-module module-null-sink load-module module-stream-restore load-module module-rescue-streams load-module module-always-sink load-module module-suspend-on-idle set-default-sink jack_out set-default-source jack_in
- Add a post-start script into qjackctl to do "pulseaudio --start" and connect the sink/source using pacmd.
ALSA had been working with the default hardware until I set up the last (autospawn=no) configuration.
Oh, wait... SuperCollider's level meter shows the laptop's built-in microphone is pushing audio in. But if I play something (e.g. SC --> JACK --> ALSA --> built-in), I hear nothing, no matter what I do in alsamixer. (Yes, I checked alsamixer and raised the level of master, headphone, speaker and PCM.)
So: built-in mic = no problem; built-in speakers/headphones = nothing.
I don't quite know where to start with this. I never had a problem with the built-in hardware -- in my previous Ubuntu installations, hw:PCH always "just worked."
TIA,
James