In the end I took your lead and installed Linux Mint and then installed the "Fully Preemptible" real-time kernel with instructions from here:  https://hungpham2511.github.io/setup/install-rtlinux/ Note, if anyone tried this, in the more recent patched kernel that I configured, the "Fully Preemptible Kernel (Real-Time)" item in the config was not found in the "Processor type and feature" menu but in "General setup". With this I got the Pd test patch running glitch free with jack configs of: 48kHz, 64 frames/period, 2 periods/buff and a latency of 2.67sec.  Cheers, On 1/31/20 11:30 AM, Christoph Kuhr wrote: Hi Iain, I always build my OS on top of linux mint. 18.3 at the moment working with the babyface. But I also build all the software that I need by myself. BR, Ck -- Diese Nachricht wurde von meinem Android Mobiltelefon mit WEB.DE Mail gesendet. Am 31.01.20, 11:05 schrieb Iain Mott <mott(a)escuta.org>rg>: Hi Christoph and list, reporting back: It seems the problems, particularly on the laptop, are related to Ubuntu. Last night I made a live USB stick of AV Linux. Booting from this both solves the problem of the USB ports and produces glitch free audio (thus far). I got ins and outs working with Pd + jack with frames/period set to 64, sample rate 48hHz, and periods/buffer 3. Latency of 4msec, so I'm happy with that (Pd gave segmentation faults on startup at lower frame rates). The Pd test (playing a tone and monitoring mic input) did much better than it did on Windows (portaudio/asio) where I still heard occasional glitches (don't remember the latency value). Christoph and others using the Scarlett, what Linux distributions are you using? hardware features? "compliant" mode? I believe it is class compliant except for configuration process.  How would one "switch from special to compliant"? I've heard of people having success using Wine to run Focusrite Control, so I'll try this too. All the best, Iain Em 31/01/2020 04:10, Christoph Kuhr escreveu: Hi Iain, no, I don't have a gen3. Is is USB Class compliant or does it come with specific hardware features? This worked for my RME babyface pro though. Hope this helps... Best Ck -- Diese Nachricht wurde von meinem Android Mobiltelefon mit WEB.DE Mail gesendet. Am 30.01.20, 11:47 schrieb Iain Mott <mott(a)escuta.org>rg>: Hi Christoph, I don't doubt for a minute that I'm doing something silly, but do you mean the monitor and headphone gain knobs on the front? Yes, they're both up. When I switch directly to windows, everything is working: pd (ASIO driver "via portaudio"), SuperCollider, Ardour, etc., but in Linux, silence.... You have a 3rd gen interface? Cheers, Iain Em 30/01/2020 07:26, Christoph Kuhr escreveu: Hi Iain, did you turn up the hardware volume? I had this problem. Someone truly evil turned it down, while I wasn't watching... ;-) BR, Ck -- Diese Nachricht wurde von meinem Android Mobiltelefon mit WEB.DE Mail gesendet. Am 30.01.20, 10:24 schrieb Iain Mott <mott(a)escuta.org>rg>: Dear Linux audio people, I have a Scarlett 18i20 3rd Gen interface which I'm trying to use on a recent Samsung laptop with Ubuntu 19.04. The 3rd gen devices are apparently shipped in non-functional "MSD" mode, so I registered and activated the device using Windows 10 following the instructions on the Focusrite website. Tested it there with Ableton Live Lite (provided via registration of the device) and also Ardour. It works fine. To get it to work on Ardour it was necessary to use the ASIO driver in the Ardour audio configuration. I had removed ASIO4ALL before installing the Focusrite/Scarlett software as suggested, so perhaps this driver came with Focusrite install. Now with the device apparently configured and the routing done in Windows using the Focusrite Control software (i thinks that's the name, I had selected output channels 1 and 2 to connect with the monitors/headphone jack), I returned to Linux. The Scarlett device is detected by lsusb, qjackctl and pavucontrol. Jack runs with no errors when the Scarlett is selected as the i/o device and all the correct channels appear in the Connect window. No sound however is heard through the phone jack, nor if i plug the phones directly in to the output jacks at the back. I tested using VLC configured for Jack output and also with pd -jack. With jack turned off and with VLC audio out set to pulsaudio, I set the Scarlett 18i20 as the preferred device in pavucontrol. With VLC playing the output VU meter for the Scarlett is active in pavucontrol but there is still no sound coming out of the device itself. Has anyone managed to get a 3rd generation Scarlett to work on Linux? Can anyone suggest please what I can do? Thanks! Iain PS. i did see an unresolved thread on this list last year about a 3rd gen Scarlett. I'll send a message to the author to see if the problem was fixed. _______________________________________________ Linux-audio-user mailing list Linux-audio-user(a)lists.linuxaudio.org https://lists.linuxaudio.org/listinfo/linux-audio-user