Hi Len, * Len Ovens <len@xxxxxxxxxxxxx> [2025-02-09 17:45]: [...] > Jackd is a manually set up utility, it is told the device name at start and > as such, it has no idea what to do when that device vanishes. It is possible > with the tools supplied to tell jack to change it's device or backend while > running via dbus. I have had varying amounts of success doing this after the > USB device has been pulled. I would guess that because it is possible to > change the device like this, jackdbus continues to run in hopes something > else will happen. following up your kind reply, I discovered that I had disabled the "JACK D-Bus interface" in qjackctl and enabled it now. I am still wondering about the difference between qjackctl's "JACK D-Bus interface" and its "D-Bus interface" by the way. Enabled both. Now qjackctl will apparently launch jackdbus instead of jackd. Unplugging the devuce while jackdbus runs will yield ERROR: ALSA: capture device disconnected ERROR: JackAudioDriver::ProcessAsync: read error, stopping... and jackdbus keeps running. Qjackctl will show "started" status. Clicking onto its "Stop" button, will freeze qjackctl for a long time until it posts: Client deactivated. D-BUS: JACK server is stopping... ERROR: JackPosixProcessSync::LockedTimedWait error usec = 20000000 err = Connection timed out ERROR: JackEngine::ClientDeactivate wait error ref = 3 name = qjackctl ERROR: JackPosixProcessSync::LockedTimedWait error usec = 4000000 err = Connection timed out ERROR: JackEngine::ClientCloseAux wait error ref = 3 Client 'qjackctl' with PID 1847586 is out Stopping jack server... ERROR: JackPosixProcessSync::LockedTimedWait error usec = 20000000 err = Connection timed out ERROR: JackEngine::ClientDeactivate wait error ref = 2 name = dbusapi ERROR: failed to deactivate dbusapi jack client. error is -1 2025: Client 'system' with PID 0 is out D-BUS: JACK server was stopped (org.jackaudio.service aka jackdbus). ERROR: JackPosixProcessSync::LockedTimedWait error usec = 4000000 err = Connection timed out ERROR: JackEngine::ClientCloseAux wait error ref = 2 ERROR: ALSA: channel flush for playback failed (No such device) ERROR: Cannot stop driver ERROR: control open "hw:UA25" (No such device) ERROR: control open "hw:UA25" (No such device) Jackdbus is still running, also when quitting qjackctl. Reconnecting the usb device and starting via a new qjackctl will not work, reporting D-BUS: JACK server could not be started. Sorry Cannot connect to server socket err = No such file or directory Cannot connect to server request channel jack server is not running or cannot be started JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock Cannot connect to server socket err = No such file or directory Cannot connect to server request channel jack server is not running or cannot be started JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock Could not connect to JACK server as client. - Overall operation failed. - Unable to connect to server. Please check the messages window for more info. Cannot connect to server socket err = No such file or directory Cannot connect to server request channel jack server is not running or cannot be started JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock Starting jack server... JACK server starting in realtime mode with priority 10 self-connect-mode is "Don't restrict self connect requests" ERROR: cannot register object path "/org/freedesktop/ReserveDevice1/Audio2": A handler is already registered for /org/freedesktop/ReserveDevice1/Audio2 ERROR: Failed to acquire device name : Audio2 error : A handler is already registered for /org/freedesktop/ReserveDevice1/Audio2 ERROR: Audio device hw:UA25 cannot be acquired... ERROR: Cannot initialize driver ERROR: JackServer::Open failed with -1 ERROR: Failed to open server Saving settings to "/home/peter/.config/jack/conf.xml" ... So this is basically the same behavior as with jackd before. I am curious what the intended behavior with jackdbus and qjackctl is supposed to be, given that it all is set up correctly. I might look closer into dbus syslogs unless someone tells me that there are certain usb audio cards, which do not signal to dbus properly. > Basically, a device vanishing in an audio context is a system failure. USB > might be designed for hot plugging but jackd is not. Good point Len! I find that jackd/jackdbus should exit nevertheless in such cases. Again, thanks for the help! best, P _______________________________________________ Linux-audio-user mailing list -- linux-audio-user@xxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to linux-audio-user-leave@xxxxxxxxxxxxxxxxxxxx
