Flat line when recording Scarlett 2i2 playback

Hi. I have a similar problem.

Kit is HP laptop, windows 8.1, and Focusrite Scarlett 2i2 USB audio interface. Focusrite drivers installed. Audacity 2.1.2 installed fine via exe. file. 2i2 shows up correctly as record / play device in Audacity, box in between says Stereo etc, but flat line on record / monitor. Bit rate matches in Audacity / sound settings.

2i2 is set to default device for playback and record in the Windows sound settings, and I have perfect sound output with streaming / music files / CDs from 2i2 output jacks / headphones. Just can’t get sound picked up by Audacity! Any ideas what I am missing?

PS The box to R of the record / play device indicators defaults to MME; I tried Windows Direct Sound and WASAPI (no idea what this is! - can someone educate me?) but no joy.

You don’t. You have a different operating system and different hardware, so I started a new topic for you with a relevant title.

You probably mean “sample rate”.

What exactly are you connecting to the Scarlett that you want to record, and which Scarlett input are you connecting to?

Can you hear that input in the Scarlett headphones?

See Audacity Manual.


Gale

Hi Gale, thanks for the response - and tidy-up! Yes, I meant sample rate.

What exactly are you connecting to the Scarlett that you want to record, and which Scarlett input are you connecting to?

The Scarlett has two mic/instrument inputs on the front, which I am not currently using, and the USB connection to the PC (via USB 2.0), to allow it to act as external sound card. Nothing else. I want to record items of streamed radio coming through the 2i2 ext audio interface.

Can you hear that input in the Scarlett headphones?

Plugging the headphones into the 2i2 I can hear everything perfectly - streamed radio, Spotify, CDs playing on the laptop, stored music files from laptop or home network - and I can output this to my amp/speaker system via the 2i2 analogue output jacks on the back. The only switches are the line/instrument sliders for each mic input -set to line.

I’ve perused the manual (thanks for link) to no avail. I’ve used earlier versions of Audacity for years on my desktop PC, though not with an external sound card - thought I knew my way around the various settings, but it seems that I don’t! I’ve read on other blogs that users have configured the 2i2 to “work perfectly” with Audacity (tho’ sadly no version/system/settings details that I can unearth).

Any other info that would be helpful?

Andrew

If you were wanting to record computer playback from the built-in sound device you would if available choose the “stereo mix” or “what U hear” recording device in Audacity’s Device Toolbar. Stereo mix or what U hear should work with any host (MME, Windows DirectSound or Windows WASAPI).

However for recording playback from an external device you must use Windows WASAPI host. Set Recording Device to Scarlett USB Audio (loopback) and Playback Device to Scarlett USB Audio. I don’t know what exact name Scarlett shows up as.

When first recording, play the song before pressing Record in Audacity.


Gale

Thank you, Gale, I’ve sussed it now. With WASAPI and loopback it works fine.

The bit that (for me) was counter-intuitive was that under Recording Device I had to select “Scarlett 2i2 LINE OUT [my capitals for emphasis] (loopback)”; I was expecting the Recording setting to be a Line IN - ie into Audacity - which was the default setting. Playback is set to “Scarlett 2i2 Line Out” also. With this arrangement the recording and playback slider controls are linked as described in the tutorial. Audacity monitors the signal, once clicked on or enabled, even if the record button is not clicked, which is better still, letting one adjust levels before recording.

So if I understand things correctly Line In/Out refers to the line in/out of the external audio interface? - in which case I would have expected the playback from Audacity to require a Line IN (to the external audio interface) setting!! I may still be confused by the signal path here. Presumably during recording the loopback extracts the digital signal coming out of the soundcard just before the DAC stage that then sends it to the output jacks / headphones. Is this right? How does the playback path work?

None of this really matters if it works, of course - but I would like to understand what is going on purely as a matter of intellectual pride!

The naming is correct. You are recording what is coming out of Scarlett (playback), not what is going into it.

Yes, WASAPI loopback is digital, without the extra conversion to analogue and back to digital that you get with stereo mix.

All sounds are captured. It is not an exclusive path only from the app playing the song. So if you receive an alert and there is a system ding, you will record the ding.

If you want technical detail: Loopback Recording - Win32 apps | Microsoft Learn.


Gale

Thanks for your interest and reply Gale.

Don’t worry, I’ve turned system sounds off. Technical link was way over my head!