Drop outs when moving mouse etc.

I’m just building studio setup using Ubuntu Studio 10.04 (Lucid), Echo AudioFire 12 (12 line in/ line out FireWire) and Ardour. Computer used is Fujitsu Siemens Pi-3630, Intel 4 core CPU Q8300, GeForce (Zogis GT220 ?), full HD resolution. All preparations for using preempt kernel are done like suggested by Ubuntu documentation. I have been succesful with test recording. There is still some work to do with my setup:

  1. Moving mouse will cause Ardour stop a moment, counter does not progress and audible drop out can be heard. Any idea what could be done ? Problem may be related to usb mouse getting too much attention / priority or screen update things, difficult to guess. Maybe someone knows this already ?

  2. Strange video corruption sometimes: Thin vertical black lines covering small part of Ardour window on the right side. Screen copies are available.

  3. Starting another instance of Ardour (by double clicking a different project file) by accident reulted in a minor snafu / mess: Could not save project and something else.

  4. More hassle noticed after that accidental starting second instance of Ardour: Started to to get some messages “Ardour responding too slowly for JACK”. I had no exact idea how badly my setuo was messed but connections (patching) shown by “qjackctrl” were lost, too. Next I did not load “qkackctrl” at all but loaded “Jack” manually on the command line (terminal). Started Ardour and used “Patchage” utility to create connections between “Ardour” and “System”. Now it works again — don’t ask me why. “Not able to save project” -things made me a bit worried.

Suggestion: Is it possible to add some code to beginning of Ardour to check whether it’s the only running instance and double check if user actually wants to start another instance ?

I did some further testing with qjackctrl. I guess problem is not related to Ardour at all: Selecting small buffer size in Jack Control will result xruns when moving mouse — no Ardour loaded ! On the contrary, xruns can (?) be avoided using big buffer but that will be equally reflected to high latency. I think my Intel Q8300 ( 4 core — fast enough) computer should be able to cope with small buffer, using big buffer is just hiding the problem.

Good ideas for testing / fixing that are warmly welcome !

Ooops… I decided to upgrade to Ubuntu Studio 10.10. Everything fine except FireWire does not work any more at all.

FFADO diagnostic utility 2.999.0-

© 2008 Pieter Palmers

=== CHECK ===
Base system…
kernel version… 2.6.32-25-preempt
FIXME: implement test for RT kernel
RT patched… False
old 1394 stack present… True
old 1394 stack loaded… False
old 1394 stack active… False
new 1394 stack present… True
new 1394 stack loaded… True
new 1394 stack active… True
/dev/raw1394 node present. True
/dev/raw1394 permissions… True
.
.
=== REPORT ===
FireWire kernel drivers:

The new FireWire kernel stack is loaded.
This stack is not supported by FFADO. Please use the old stack.

Nothing appears to work with FireWire now, can not start ffado-dbus-server (and use ffado mixer).

ffado-test Discover

FFADO test and diagnostic utility
Part of the FFADO project – www.ffado.org
Version: 2.999.0-
© 2008, Daniel Wagner, Pieter Palmers
This program comes with ABSOLUTELY NO WARRANTY.

Could not initialize device manager
02857930292: Fatal (devicemanager.cpp)[ 191] initialize: No firewire adapters (ports) found.
no message buffer overruns

Any ideas what’s next ?

[Solved]

Thanks Paul. I already paid attention to that sentence and there are actually two stacks loaded in new 10.10 Ubuntu Studio. Current new stack does not work so far for audio (at least I didn’t succeed) but I found experimentally a temporary work around exactly the way you said. All drivers of new stack can be unloaded and after that can load the older ones which are actually needed. I made a small script to do that after each boot up. I’l paste it here:

#!/bin/sh
#Unloads all FireWire drivers and loads older FireWire stack
#30.10.2010 by “ajaaskel” @ Ubuntu Forum
sudo modprobe -r video1394
sudo modprobe -r firewire-sbp2
sudo modprobe -r sbp2
sudo modprobe -r dv1394
sudo modprobe -r firewire-ohci
sudo modprobe -r raw1394
sudo modprobe -r ohci1394
sudo modprobe raw1394
sudo modprobe dv1394
sudo modprobe sbp2
sudo modprobe dv1394
sudo modprobe video1394
echo
echo ‘*** Load also ffado-dbus-server if you need ffado-mixer. ***’
echo
sleep 5

Paste that into your editor, save it as fw.sh, set “allow execution” on and you can run it in terminal with command

./fw.sh

(don’t forget dot slash in the beginning…)

Drivers coming with 10.10 are a lot better, I’m not sure whether that is related to stack itself or “jack”. Mouse dropouts are gone and I was able to use even 0.7 ms latency ! Earlier with 10.04 latencies close to one millisecond made xruns high at Jack Control ---- Ardour not yet loaded :slight_smile:
Ubuntu Studio 10.10 looks surprising good already now. One small thing to remember: When booting Ubuntu Studio it’s better remember to select “preempt” kernel, not the standard one which is also included and offered at boot up as default.

I hope this helps someone else with Ubuntu Studio 10.10.

From the output you pasted:

FireWire kernel drivers:

The new FireWire kernel stack is loaded.
This stack is not supported by FFADO. Please use the old stack.

You’ll need to find some people experienced with the version of Ubuntu you are using and also FFADO. It has the wrong kernel stack for firewire audio usage.

ffado-dbus-server is needed if you use ffado mixer, a kind of monitor mixer which allows you to define pass-trough from any line in to line out in AudioFire 12. Settings can be stored to AF12 and it will remember them (written to memory of AF12). You can start ffado-dbus-server from command line just typing

ffado-dbus-server

Permanent change: You can change Ubuntu Studio 10.10 to use permanently that older FireWire stack (which works for FireWire audio). Procedure was described at Ubuntu Forum and includes editing /etc/modeprobe.d/blacklist-firewire.conf, running “sudo update-initramfs -k all -u” to activate changes and booting after that. I tested that procedure succesfully, no need to use my script any more after that. That script is however still useful for temporary testing.

FireWire is ok in “Natty” Ubuntu Studio 11.04. No special tricks are needed. Only low latency kernel appear to be mandatory add-on in order to avoid xruns.