pop at the beginning of recording any new track

i am running ubuntu 16.04 LTS Audacity 2.3.0 through UFX1204 USB for both recording and playback. I believe this saw installed from distribution’s release.

Whenever I start recording I get a big pop ~ 1 sec. I know I can delete it, but then as I add tracks I have to keep trimming the front every time. i have tried this with the playback track off on the UFX, and then I can’t hear it but I can see it.

Is your silence at zero on the timeline?

The wave on the right is normal. If you stop talking do your waves settle to zero? They can be off either up or down.

Or before you remove the pop, does the blue line not start at zero?

Converting from analog to digital is performed by electronic components. They don’t have to work right.

Koz

OK I might be using the wrong terminology. You can see in the screen shot what I mean. Thanks
Screenshot from 2018-11-04 14-05-56.png

Try setting the default recording / playback device in the system “Sound Settings” to the UFX1204, and then set the devices to “default” in the device toolbar. If that appears to work, test it thoroughly - on some machines this can make Audacity prone to freezing but on other machines it can be the best option.

I apologize in advance for my ignorance with there to find things. Under edit preferences:Devices
Playback Device: UFX1204: USB Audio (hw:1,0) (only UFX1204 choice)
Recording Device: UFX1204: USB Audio (hw:1,0):line:1

When I go to change the tool bar, I get a grayout stall, but then it comes back. Recording defaoult has several choices. I selected default: Line:1.

OK now I am getting no input signal. I changed “mic” on toolbar to UFX1204:USBAudio (hw:1,0):line:1. Now getting signal.

Still having issue. See attached.
Screenshot from 2018-11-04 15-50-07.png

What do you get if you run this in a terminal:

pactl info
Server String: unix:/run/user/1000/pulse/native
Library Protocol Version: 30
Server Protocol Version: 30
Is Local: yes
Client Index: 73
Tile Size: 65472
User Name: lori
Host Name: lori-GRCCS-AudioCustom
Server Name: pulseaudio
Server Version: 8.0
Default Sample Specification: s16le 2ch 44100Hz
Default Channel Map: front-left,front-right
Default Sink: alsa_output.usb-BEHRINGER_UFX1204_0x15640036eee-00.analog-surround-40
Default Source: alsa_input.pci-0000_00_1b.0.analog-stereo
Cookie: 1674:1920
Default Sink: alsa_output.usb-BEHRINGER_UFX1204_0x15640036eee-00.analog-surround-40
Default Source: alsa_input.pci-0000_00_1b.0.analog-stereo

That shows that PulseAudio is set to use the UFX1204 as the output device and your built-in sound card (analog-stereo) as the recording device.

If you run this command, do you see the PulseAudio volume control?

pavucontrol

yes

I presume that you are trying to record from analog inputs to the UFX1204?

One more bit of information required:

  1. Ensure that no audio applications (such as Skype) are set to start on log-in.
  2. Shut down the computer and reboot
  3. Launch Audacity
  4. Open “Audio Device Info” from the Help menu, and save the info somewhere convenient
  5. Attach the saved txt file to your reply.