Hi Fons,
On 27/10/2025 14:55, Fons Adriaensen wrote:
On Sun, Oct 26, 2025 at 03:21:31PM +0000, Bill Purvis wrote:


I've been having problems with connections between jack clients dropping
out.

Do you mean connections drop out without any reason while the ports
still exist ? This shouldn't happen unless something is doing this
explicitly. I've never noticed such a thing in +20 years of using
Jack. What I have seen is e.g. qjackctl's connection window showing
false information.

So the first thing to do would be to find out why this happens...
My current thinking is that the U-DAC8 is occasionally restarting, possibly a loose
USB socket. I've just switched to a Gigaport-eX, which has a USB-C connector and will
keep an eye on it. I've now installed a rather crude monitor script that attempt to reconnect
if it detects any such interruption, i.e. the connections dropping. 
Jack also has a port_(dis)connect callback, it would be interesting
to see if this is called. All you'd need is a simple client that
using this callback and printing out its arguments.
I'm currently playing about with various jack callbacks, just need to be careful
about what I do in the callbacks. I'm trying to avoid things like qjackctl, qpwgraph,
as the system normally runs headless. Sticking with little bits of C code and shell
scripts. I do use qpwgraph for debugging things as I do have the monitor plugged in 
then, but 'normal' usage is just to power up the PC and start the organ software from
an autostart script. 
-- 
+---------------------------------------------+
| Bill Purvis          G8DIO                  |
| bill@billp.org                              |
+---------------------------------------------+