 Just testing recording into Audacity from a Fender GT200 Mustang amp via USB. I am getting periodic audio drop outs approx once a second.  … The only way I can select the Mustang USB amp as the recording device is by selecting ALSA in Audacity > Preferences > Devices > Host. If I select Jack in Host there is no option to select the Mustang
[12:52] <studiobot> and no sound recorder. Any clues as what might be the cause gratefully received.   …  This is what I see as I launch Audacity in terminal.  … user@user-System-Product-Name:~$ audacity … Error opening file /home/user/.lv2/organ_roussel.sf2/manifest.ttl (Not a directory) … lilv_world_load_file(): error: Error loading file `file:///home/user/.lv2/orga
[12:52] <studiobot> n_roussel.sf2/manifest.ttl' … lilv_world_load_bundle(): error: Error reading file:///home/user/.lv2/organ_roussel.sf2/manifest.ttl … ALSA lib pcm_dsnoop.c:618:(snd_pcm_dsnoop_open) unable to open slave … ALSA lib pcm_dmix.c:1052:(snd_pcm_dmix_open) unable to open slave … ALSA lib pcm.c:2495:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear … ALSA
[12:52] <studiobot> lib pcm.c:2495:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe … ALSA lib pcm.c:2495:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side … ALSA lib pcm_dmix.c:1052:(snd_pcm_dmix_open) unable to open slave … 12:19:15: Debug: ScreenToClient cannot work when toplevel window is not shown … 12:19:15: Debug: ScreenToClient cannot work when toplev
[12:52] <studiobot> el window is not shown … 12:19:15: Debug: ScreenToClient cannot work when toplevel window is not shown … 12:19:15: Debug: ScreenToClient cannot work when toplevel window is not shown … 12:19:15: Debug: ScreenToClient cannot work when toplevel window is not shown … 12:19:15: Debug: ScreenToClient cannot work when toplevel window is not shown … 12:19
 (Photo, 800x679) https://i.imgur.com/YN7fA8K.jpg This is my US Control settings.
 (Photo, 748x510) https://i.imgur.com/0LxE72C.jpg
 And a screenshot Audacity Devices tab.
 (Audio, 32s)http://studiobot.ericheickmeyer.com:9090/YZbn0EdO/file_61.mp3
 And here is a brief MP3 sample of the dropouts.
[14:06] <OvenWerks> Chris: You are using hdmi as output, is that on purpose?
[14:08] <OvenWerks> Chris: Are you sure your USB device handles 44100? (some only do 48000)
 No, I am using a Focusrite USB audio interface (which is listed as 'USB 0,0' in USB devices). The Nvidia HDMI was the default selection, which I ignore. As I understand it (?), if a USB is device selected in 'USB Devices', it takes precedence over non-USB Master device. I do use the Nvidia audio for my second screen ( lTV screen for video e
[15:12] <studiobot> diting).   … The Focusrite interface dies 44100 OK.
[15:13] <OvenWerks> Chris ok sounds good...
 Thanks.
[15:16] <OvenWerks> Is the mustang plugged in as well?
[15:21] <OvenWerks> Chris: if the mustang is plugged in, can you post the url given by: jack_lsp |pastebinit
 Yes, the Mustang is plugged into the desktop pc usb port. … Here is output of jack_lsp. … user@user-System-Product-Name:~$ jack_lsp … system:capture_1 … system:capture_2 … system:capture_3 … system:capture_4 … system:capture_5 … system:capture_6 … system:playback_1 … system:playback_2 … system:playback_3 … system:playback_4 … system:playbac
[15:40] <studiobot> k_5 … system:playback_6 … PulseOut:front-left … PulseOut:front-right … PulseIn:front-left … PulseIn:front-right … a2j:Midi Through [14] (capture): Midi Through Port-0 … a2j:Midi Through [14] (playback): Midi Through Port-0 … a2j:Keystation 88 [20] (capture): Keystation 88 MIDI 1 … a2j:Keystation 88 [20] (playback): Keystation 88 MIDI 1 … a2j:Keysta
[15:40] <studiobot> tion 88 [20] (capture): Keystation 88 MIDI 2 … a2j:Scarlett 6i6 USB [24] (capture): Scarlett 6i6 USB MIDI 1 … a2j:Scarlett 6i6 USB [24] (playback): Scarlett 6i6 USB MIDI 1 … user@user-System-Product-Name:~$ 
[15:40] <OvenWerks> Chris I asked for the output of  jack_lsp |pastebinit
[15:41] <OvenWerks> This should have been a one line URL not a set of lines
[15:42] <OvenWerks> In any case I don't see the mustang.
[15:43] <OvenWerks> This next command is all one line in the terminal:
[15:43] <OvenWerks> cd /tmp && wget http://jackaudio.org/downloads/adevices.sh && bash ./adevices.sh |pastebinit
[15:43] <OvenWerks> Again it should only put out one line.
[15:44] <OvenWerks> Hmm it gave more here, but I only want the last line
[15:44] <OvenWerks> The one that says:
[15:44] <OvenWerks> http://paste.ubuntu.com/etc
 http://paste.ubuntu.com/p/9P2xKymZYS/
[15:56] <OvenWerks> in a terminal try: zita-a2j -d hw:Audio,0,0
[15:57] <OvenWerks> Chris ^^
 Ok
[16:01] <OvenWerks> Chris: if that doesn't error out, in another terminal type: jack_lsp |pastebinit
[16:01] <OvenWerks> and send the url
 user@user-System-Product-Name:~$  zita-a2j -d hw:Audio,0,0,0 … ALSA lib conf.c:4858:(parse_args) Unknown parameter 3 … ALSA lib conf.c:4991:(snd_config_expand) Parse arguments error: No such file or directory … ALSA lib pcm.c:2495:(snd_pcm_open_noupdate) Unknown PCM hw:Audio,0,0,0 … Can't open ALSA capture device 'hw:Audio,0,0,0'. … user@us
[16:03] <studiobot> er-System-Product-Name:~$
 Did I make an error?
[16:03] <Eickmeyer> Pro tip: put a space after the pipe.
[16:03] <OvenWerks> one too many 0s
[16:04] <OvenWerks> zita-a2j -d hw:Audio,0,0 is the line you want
[16:04] <OvenWerks> just two 0,0 not 0,0,0
 Sorry.
[16:05] <OvenWerks> Chris no problem
 The terminal is reporting 'starting synchronisation' but then nothing happens.
[16:09] <OvenWerks> Chris that is good
[16:09] <OvenWerks> Just leave that terminal running for now and open another terminal
[16:10] <OvenWerks> in the second terminal type: jack_lsp |pastebinit
 Ok second one open
[16:11] <OvenWerks> Chris: in the second terminal type jack_lsp |pastebinit
[16:11] <OvenWerks> it should give a web page URL
 http://paste.ubuntu.com/p/dWngFFjVVk/
[16:13] <OvenWerks> Chris: Great, your mustang sound should be the jack port called zita-a2j:capture_1 and 2
[16:13] <OvenWerks> Now the question is why that did not happen automatically
 Yes, that now appears in the Audacity recording menu. …  I will try it.
 Yep, it is perfect. No drop outs and quality great. Many thanks!
[16:18] <OvenWerks> Chris are you interested in trouble shooting farther?
 Yes. Of course.
[16:21] <OvenWerks> in the first terminal where you ran zita-a2j, hold the control key down and press c at the same time.
[16:22] <OvenWerks> this should stop zita-a2j and give you the command prompt again.
 Ok
 Done
[16:23] <OvenWerks> then try: zita-a2j -d hw:Audio,0,0 -r 44100
[16:23] <OvenWerks> in that same terminal
[16:24] <OvenWerks> (in case you are interested, we were running it at 48000 before)
[16:26] <OvenWerks> Chris the above line should work the same as the last time giving you the syncing message
 Response is  … Can't open ALSA capture device 'hw: Audio,0,0'
[16:28] <OvenWerks> @Chris: this tells me that your mustang probably only runs at 48000
[16:28] <OvenWerks> If you change the setting on your focus rite to 48000 then restart jack in controls you should see both
 I find that off because 44100 is CD standard.
 Odd
 Simethi g guitarist would need.
[16:29] <OvenWerks> 48000 is the digital standard, 44100 is only for CDs and nothing else. DVDs, broadcast, videos , windows all use 48000
[16:30] <Eickmeyer> If you're burning to CD, then most CD burning applications are smart enough to downsample.
 Doesn't that change the pitch?
[16:30] <OvenWerks> @Chris: no,
[16:31] <OvenWerks> SRC preserves pitch
 Or is it speed?
[16:31] <OvenWerks> SRC also preserves speed.
 Ok
[16:32] <OvenWerks> @Chris, FYI the old soundblaster audio devices recorded everything at 48000 and then if the user asked the card for anything else they used a hardware SRC to change it.
 I will have log into Windows to change the Focusrite sample rate. Let me get the laptop going
[16:33] <OvenWerks> That was the AC97 standard. The HDA stanard still uses a 48000 buss speed but does allow the ADC to run at other rates
 Ok
[16:34] <OvenWerks> @Chris, you shouldn't have to... (I could be wrong) it should accept jack starting at 48000
[16:37]  * OvenWerks will be back in a sec... short Dog walk required...
[16:42] <OvenWerks> @Chris: when you get it starting at 48000, the mustang should show up as Audio,0,0-in
 While in Windows, I realised that I had accidentally forgotten to set 44100 as the sample rate in Focusrite  last time I messed with it. I set it to factory defaults which is 48000 and must have forgotten to change it. 😎
[16:49] <Eickmeyer> @Chris: Hold up... the focusrite has to be reconfigured using its windows app for the sample rate?? Nearly every USB audio interface I've ever used (except audio mixers, where you set the sample rate on the device) adapts to whatever sample rate it is given.
[16:50] <OvenWerks> Eickmeyer: the focusrite has required extensions for some things in the linux driver
[16:51] <OvenWerks> but yeah, I would expect jack to be able to at least set sample rate
[16:51] <OvenWerks> (in order to be macos compliant)
[16:52] <Eickmeyer> Right, that's where I'm concerned. If this is indeed the case, then that explains the problem people have been having with focusrites lately.
[16:53]  * OvenWerks also notes that while jackd does request a change of sample rate, if the device is unable to do so, jackd is not aware that the device is running in a different rate than asked for.
[16:55] <OvenWerks> This does not stop jackd from operating.... but it does lead to odd things if an ardour session is recorded with jackd "thinking" is has the device set to 48k when in fact the device is at 44k1. The next time jackd may be able to set the device (or another) to 48k and then the pitch/speed will be wrong.
 There is no Linux equivalent of Focusrite Control app used to set up the internal routing and other settings, including sample rate. So, you have to boot into Windows and set it. The device then 'remembers' the last settings when you switch to Linux.
 I have rebooted Linux and the zita option is no longer available in Audacity when Jack is selected as Host.
[17:09] <OvenWerks> @Chris: so having set the focusrite to 48000 and restarted on the linux box at 48000, do you see your mustang now?
 In US Controls, there is now a USB 0,0 Playback and Capture + Usb audio
[17:15] <OvenWerks> Audio is the mustang, USB is the focusrite
 Sorry. … It is 'USB 0,0 Playback and Capture (USB Audio)' option, which wasn't there before.
 That is in addition to the 'USB, 0,0'.
[17:17] <OvenWerks> Both focusrite and Fender could have set these names to something that gives a better hint to what they are. They probably just used the default name on the chip rather than customizing it.
 I will select the new option and see if it works.
[17:18] <OvenWerks> I would still use USB,0,0 as the USB master. The mustang should just show up so long as the rate is set to 48000
[17:19] <OvenWerks> It is mostly best (or at least, less confusing) to use your output device as the jack master
[17:20] <OvenWerks> That way most audio programs auto connect to the right outputs ...
 The new option doesn't stick after 'apply audio settings'  is clicked. It goes back to USB,0,0.
[17:23] <OvenWerks> @Chris: I am not sure, but There were some versions of controls where you had to apply and then restart
[17:23] <OvenWerks> But USB,0,0 is probably right anyway.
 In Audacity settings, if Jack is selected as Host, there is a new option ' Audio, 0,0-in'. I will test it.
 Yes, it is fine. No drop outs and audio fine.
[17:30] <OvenWerks> @Chris: I think you at the, thats as good as it gets point.
 There is now no Mustang  option if ALSA is selected as Host but that is not a big deal.
[17:33] <OvenWerks> @Chris: it always either jackd or alsa, to see a device in alsa, first jack needs to be stopped
 Many thanks for all your help. Sorting out my muddle!
[17:34] <OvenWerks> Jackd locks any device it uses
 Understood.
[17:34] <OvenWerks> Not a problem.... Time for another controls mod...