Hi Aleksej,

here is the logfile of OBS Studio:
May be you can get some information here.
-------------------------------------------------------------------------------------
15:50:39.995: Using EGL/X11
15:50:39.996: CPU Name: 11th Gen Intel(R) Core(TM) i7-11390H @ 3.40GHz
15:50:39.996: CPU Speed: 399.997MHz
15:50:39.998: Physical Cores: 4, Logical Cores: 8
15:50:39.998: Physical Memory: 64088MB Total, 58494MB Free
15:50:39.998: Kernel Version: Linux 6.11.10-gnu
15:50:39.998: Distribution: "Guix System" Unknown
15:50:39.999: Desktop Environment: MATE (mate)
15:50:39.999: Session Type: x11
15:50:39.999: Window System: X11.0, Vendor: The X.Org Foundation, 
Version: 1.21.1
15:50:40.005: Qt Version: 6.6.3 (runtime), 6.6.3 (compiled)
15:50:40.005: Portable mode: false
15:50:40.179: OBS 30.1.2 (linux)
15:50:40.179: ---------------------------------
15:50:40.182: ---------------------------------
15:50:40.182: audio settings reset:
15:50:40.182: 	samples per sec: 48000
15:50:40.182: 	speakers:        2
15:50:40.182: 	max buffering:   960 milliseconds
15:50:40.182: 	buffering type:  dynamically increasing
15:50:40.221: ---------------------------------
15:50:40.221: Initializing OpenGL...
15:50:40.565: Loading up OpenGL on adapter Intel Mesa Intel(R) Xe 
Graphics (TGL GT2)
15:50:40.565: OpenGL loaded successfully, version 4.6 (Core Profile) 
Mesa 24.0.4, shading language 4.60
15:50:40.846: ---------------------------------
15:50:40.847: video settings reset:
15:50:40.847: 	base resolution:   1920x1080
15:50:40.847: 	output resolution: 640x360
15:50:40.847: 	downscale filter:  Bicubic
15:50:40.847: 	fps:               30/1
15:50:40.847: 	format:            NV12
15:50:40.847: 	YUV mode:          Rec. 709/Partial
15:50:40.847: NV12 texture support enabled
15:50:40.848: P010 texture support not available
15:50:40.868: Audio monitoring device:
15:50:40.868: 	name: Komplete Audio 1 Analog Stereo
15:50:40.868: 	id: 
alsa_output.usb-Native_Instruments_Komplete_Audio_1_0000B379-00.analog-stereo
15:50:40.868: ---------------------------------
15:50:40.912: Failed to load 'en-US' text for module: 'decklink-captions.so'
15:50:40.959: Failed to load 'en-US' text for module: 
'decklink-output-ui.so'
15:50:40.993: A DeckLink iterator could not be created.  The DeckLink 
drivers may not be installed
15:50:40.993: Failed to initialize module 'decklink.so'
15:50:42.055: [pipewire] No captures available
15:50:42.159: v4l2loopback not installed, virtual camera disabled
15:50:42.324: VAAPI: Failed to initialize display in 
vaapi_device_h264_supported
15:50:42.324: FFmpeg VAAPI H264 encoding not supported
15:50:42.325: VAAPI: Failed to initialize display in 
vaapi_device_av1_supported
15:50:42.325: FFmpeg VAAPI AV1 encoding not supported
15:50:42.326: VAAPI: Failed to initialize display in 
vaapi_device_hevc_supported
15:50:42.326: FFmpeg VAAPI HEVC encoding not supported
15:50:42.665: [obs-websocket] [obs_module_load] you can haz websockets 
(Version: 5.4.2 | RPC Version: 1)
15:50:42.665: [obs-websocket] [obs_module_load] Qt version 
(compile-time): 6.6.3 | Qt version (run-time): 6.6.3
15:50:42.665: [obs-websocket] [obs_module_load] Linked ASIO Version: 102800
15:50:42.701: [obs-websocket] [obs_module_load] Module loaded.
15:50:42.856: [vlc-video]: VLC 3.0.21 Vetinari found, VLC video source 
enabled
15:50:42.857: ---------------------------------
15:50:42.857:   Loaded Modules:
15:50:42.857:     vlc-video.so
15:50:42.857:     text-freetype2.so
15:50:42.857:     rtmp-services.so
15:50:42.857:     obs-x264.so
15:50:42.857:     obs-websocket.so
15:50:42.857:     obs-webrtc.so
15:50:42.857:     obs-vst.so
15:50:42.857:     obs-transitions.so
15:50:42.857:     obs-outputs.so
15:50:42.857:     obs-filters.so
15:50:42.857:     obs-ffmpeg.so
15:50:42.857:     linux-v4l2.so
15:50:42.858:     linux-pulseaudio.so
15:50:42.858:     linux-pipewire.so
15:50:42.858:     linux-capture.so
15:50:42.858:     linux-alsa.so
15:50:42.858:     image-source.so
15:50:42.858:     frontend-tools.so
15:50:42.858:     decklink-output-ui.so
15:50:42.858:     decklink-captions.so
15:50:42.858: ---------------------------------
15:50:42.858: ==== Startup complete 
===============================================
15:50:42.875: Switched to Preview/Program mode
15:50:42.875: ------------------------------------------------
15:50:42.979: All scene data cleared
15:50:42.979: ------------------------------------------------
15:50:42.999: pulse-input: Server name: 'pulseaudio 16.1'
15:50:43.000: pulse-input: Audio format: s32le, 44100 Hz, 2 channels
15:50:43.001: pulse-input: Started recording from 
'alsa_output.usb-Native_Instruments_Komplete_Audio_1_0000B379-00.analog-stereo.monitor'
15:50:43.003: [Loaded global audio device]: 'Desktop-Audio'
15:50:43.005: pulse-input: Server name: 'pulseaudio 16.1'
15:50:43.006: pulse-input: Audio format: s32le, 44100 Hz, 2 channels
15:50:43.006: pulse-input: Started recording from 
'alsa_output.usb-Native_Instruments_Komplete_Audio_1_0000B379-00.analog-stereo.monitor'
15:50:43.006: [Loaded global audio device]: 'Desktop-Audio 2'
15:50:43.008: pulse-input: Server name: 'pulseaudio 16.1'
15:50:43.009: pulse-input: Audio format: s32le, 44100 Hz, 2 channels
15:50:43.009: pulse-input: Started recording from 
'alsa_input.usb-Native_Instruments_Komplete_Audio_1_0000B379-00.analog-stereo'
15:50:43.010: [Loaded global audio device]: 'Mikrofon-/AUX-Audio'
15:50:43.014: pulse-input: Server name: 'pulseaudio 16.1'
15:50:43.015: pulse-input: Audio format: s32le, 44100 Hz, 2 channels
15:50:43.015: pulse-input: Started recording from 
'alsa_input.usb-Native_Instruments_Komplete_Audio_1_0000B379-00.analog-stereo'
15:50:43.016: [Loaded global audio device]: 'Mikrofon-/AUX-Audio 2'
15:50:43.029: alsa-input: PCM 'default' rate set to 44100
15:50:43.029: alsa-input: PCM 'default' channels set to 2
15:50:43.037: pulse-input: Server name: 'pulseaudio 16.1'
15:50:43.038: pulse-input: Audio format: s32le, 44100 Hz, 2 channels
15:50:43.039: pulse-input: Started recording from 
'alsa_input.usb-Native_Instruments_Komplete_Audio_1_0000B379-00.analog-stereo' 
(default)
15:50:43.045: alsa-input: PCM 'default' rate set to 44100
15:50:43.045: alsa-input: PCM 'default' channels set to 2
15:50:43.053: pulse-input: Server name: 'pulseaudio 16.1'
15:50:43.054: pulse-input: Audio format: s32le, 44100 Hz, 2 channels
15:50:43.054: pulse-input: Started recording from 
'alsa_input.usb-Native_Instruments_Komplete_Audio_1_0000B379-00.analog-stereo'
15:50:43.062: alsa-input: PCM 'default' rate set to 32000
15:50:43.062: alsa-input: PCM 'default' channels set to 2
15:50:43.081: Switched to scene 'Komplete Audio 1'
15:50:43.082: User switched Program to scene 'Lieder'
15:50:43.088: ------------------------------------------------
15:50:43.088: Loaded scenes:
15:50:43.088: - scene 'Szene':
15:50:43.088: - scene 'Lieder':
15:50:43.088:     - source: 'Audioaufnahmegerät (ALSA)' (alsa_input_capture)
15:50:43.088:     - source: 'Audioeingabeaufnahme (PulseAudio)' 
(pulse_input_capture)
15:50:43.088: - scene 'Komplete Audio 1':
15:50:43.088:     - source: 'Mikrofon-/AUX-Audio' (pulse_input_capture)
15:50:43.088:     - source: 'Desktop-Audio 2' (pulse_output_capture)
15:50:43.088: - scene 'Guix with voice':
15:50:43.088:     - source: 'Audioaufnahmegerät (ALSA) 2' 
(alsa_input_capture)
15:50:43.088:     - source: 'Audioeingabeaufnahme (PulseAudio) 2' 
(pulse_input_capture)
15:50:43.089: - scene 'Audiobox USB':
15:50:43.089:     - source: 'Audioaufnahmegerät (ALSA) 3' 
(alsa_input_capture)
15:50:43.089:     - source: 'Desktop-Audio' (pulse_output_capture)
15:50:43.089:     - source: 'Mikrofon-/AUX-Audio' (pulse_input_capture)
15:50:43.089:     - source: 'Audioaufnahmegerät (ALSA)' (alsa_input_capture)
15:50:43.089: ------------------------------------------------
15:50:43.555: adding 21 milliseconds of audio buffering, total audio 
buffering is now 21 milliseconds (source: Mikrofon-/AUX-Audio)
15:50:43.555:
15:51:23.526: ---------------------------------
15:51:23.526: [x264 encoder: 'simple_video_recording'] preset: veryfast
15:51:23.526: [x264 encoder: 'simple_video_recording'] profile: high
15:51:23.527: [x264 encoder: 'simple_video_recording'] settings:
15:51:23.527: 	rate_control: CRF
15:51:23.527: 	bitrate:      0
15:51:23.527: 	buffer size:  0
15:51:23.527: 	crf:          17
15:51:23.527: 	fps_num:      30
15:51:23.527: 	fps_den:      1
15:51:23.527: 	width:        640
15:51:23.527: 	height:       360
15:51:23.527: 	keyint:       250
15:51:23.527:
15:51:23.545: ---------------------------------
15:51:23.548: [FFmpeg aac encoder: 'simple_aac_recording0'] bitrate: 
192, channels: 2, channel_layout: stereo
15:51:23.548:
15:51:23.567: ==== Recording Start 
===============================================
15:51:23.567: [ffmpeg muxer: 'simple_file_output'] Writing file 
'/home/gfp/Desktop/Lieder aufnehmen/2024-12-01 15-51-23.mkv'...
15:51:33.523: [ffmpeg muxer: 'simple_file_output'] Output of file 
'/home/gfp/Desktop/Lieder aufnehmen/2024-12-01 15-51-23.mkv' stopped
15:51:33.523: Output 'simple_file_output': stopping
15:51:33.523: Output 'simple_file_output': Total frames output: 273
15:51:33.523: Output 'simple_file_output': Total drawn frames: 297 (298 
attempted)
15:51:33.523: Output 'simple_file_output': Number of lagged frames due 
to rendering lag/stalls: 1 (0.3%)
15:51:33.524: ==== Recording Stop 
================================================
15:51:33.543: Error uninhibiting: 
GDBus.Error:org.freedesktop.DBus.Error.UnknownObject: 
GDBus.Error:org.freedesktop.DBus.Error.UnknownObject: No such object 
path 
'/org/freedesktop/portal/desktop/request/1_68/obs_inhibit_portal1321847995'
15:56:17.571: adding 21 milliseconds of audio buffering, total audio 
buffering is now 42 milliseconds (source: Audioaufnahmegerät (ALSA) 3)
15:56:17.571:

-----------------------------------------------------------------------------------

Am 01.12.24 um 15:56 schrieb gfp:
> Am 01.12.24 um 11:50 schrieb Aleksej:
>> The fact that your interface is not listed in lsusb is quite strange. 
>> For the experiment, I even tried booting from the Guix installation 
>> image, and my interface was listed in lsusb. Are you sure your 
>> interface is working? Could you try it with another USB port, PC, or 
>> distribution?
> 
> Hi Aleksei,
> 
> now it is listed in lsusb: Native Instruments Komplete Audio 1
> 
> but it doesn´t work either.
> 
> gfp@Tuxedo ~$ lsusb
> Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
> Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
> Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
> Bus 003 Device 006: ID 2109:2812 VIA Labs, Inc. VL812 Hub
> Bus 003 Device 007: ID 046d:c31c Logitech, Inc. Keyboard K120
> Bus 003 Device 008: ID 046d:c077 Logitech, Inc. Mouse
> Bus 003 Device 009: ID 17cc:1830 Native Instruments Komplete Audio 1
> Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
> Bus 004 Device 003: ID 2109:0812 VIA Labs, Inc. VL812 Hub
> 
> thanks
> 
> Gottfried