[PD] glitches when streaming UDP

Pagano, Patrick patrick.pagano at uconn.edu
Tue Jan 30 23:26:24 CET 2018

I just went through this ordeal with an MboxPro3 and ubuntu/LowLatency Kernel

the answer for me was using a FW soundcard and Cadence from KxStudios. It solved the under/overrun problem

Patrick Pagano B.S, M.F.A

Assistant Professor in Residence

Digital Media & Design

Web & Interactive Technologies

University of Connecticut, Stamford


From: Pd-list <pd-list-bounces at lists.iem.at> on behalf of Dan Wilcox <danomatika at gmail.com>
Sent: Tuesday, January 30, 2018 5:21:33 PM
To: Roman Haefeli
Cc: Pd-List
Subject: Re: [PD] glitches when streaming UDP

If you're using jack, is the jack server running without dropouts with other software? I'm only suggesting to consider sources other than Pd as well.

On Jan 30, 2018, at 9:25 PM, pd-list-request at lists.iem.at<mailto:pd-list-request at lists.iem.at> wrote:

Date: Tue, 30 Jan 2018 21:25:26 +0100
From: Roman Haefeli <reduzent at gmail.com<mailto:reduzent at gmail.com>>
To: Pd-List <pd-list at lists.iem.at<mailto:pd-list at lists.iem.at>>
Subject: Re: [PD] glitches when streaming UDP
Message-ID: <1517343926.2187.14.camel at gmail.com<mailto:1517343926.2187.14.camel at gmail.com>>
Content-Type: text/plain; charset="utf-8"

On Die, 2018-01-30 at 16:38 +0100, Dan Wilcox wrote:
Is it running with the *same* OS and settings?

As far as I can tell: yes. Same OS (Ubuntu 16.04), same Kernel (4.13.0-
32-lowlatency), both tuned so that "realtimeconfigquickscan" doesn't
complain anymore. This includes configuring /etc/security/limits.conf,
adding user to audio group, making high-precision timer /dev/hpet und
realtime clock /dev/rtc readable by members of audio group, etc. I get
stable performance with Ardour with the same qjackctl settings, with
built-in soundcard, but also with external USB sound interface on BOTH

It might be a scheduling issue with the kernel, realtime settings,
crappy networking driver, etc.

I thought about that, too. But why does it affect only Pd? On the
"troubled" machine - where everything else runs supersmooth - this
setup suffers a couple of glitches per second (jack routing):

mpv -> Pd running [adc~]-[dac~] -> system output

The probable causes you mentioned would affect other audio softwares,
too, wouldn't they?

The Pd version doesn't seem to make a difference...

Anyway, thanks for your thoughts.


Dan Wilcox

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.puredata.info/pipermail/pd-list/attachments/20180130/0dc52d13/attachment-0001.html>

More information about the Pd-list mailing list