Low recording levels - what has changed?

Online recording source volume: 100%

Audacity 3.1.3 settings.
Recording volume: 1.0
Playback volume: 1.0
Audio Host: Windows WASAPI
Recording Device: Speakers (Realtek High Definition Audio)(loopback)
Recording Channels: 2 (Stereo) Recording Channels
Playback Device: Speakers (Realtek High Definition Audio)

Realtek - Device Advanced Settings:
1 Mute the rear output device, when a front headphone plugged in. [Selected]
2 Make front and rear output devices play back two different audio streams simultaneously.
(Using front headphones)

I used to be able to set the peaks at c. -0.3, often having to reduce the recording volume to between 85 & 90%.
The waveform would have peaks just inside 1.0 & -1.0.
Is this due to a recent W10 update? A change in Audacity functionality?
Any help/advice would be appreciated.
Waveform18-08-2022.png

I believe you are correct. I just tested 2.4.2 and 3.1.3 on Windows 10 WASAPI loopback recording. They both exhibit exactly this behavior. The Audacity playback volume control seems to have no effect. Counterintuitively, the Audacity recording volume control seems to adjust the volume in my headphones, but the recording level within Audacity seems to remain unchanged.

I think this may be because I used to use MME Stereo Mix.

When I enabled Stereo Mix in MME just now (via mmsys.cpl) I do see different behaviors between 2.4.2 and 3.1.3. In 3.1.3 neither control seems to have any effect in the recording level. However in 2.4.2, the controls seem to be intertwined. If I set the both Audacity recording and playback volumes to zero, nothing gets recorded; increasing the playback volume increases the recording level but only up to about -30db. If I start with both controls set to max, then my headphones are extremely loud and the recording is obviously clipping (where the original wasn’t). Adjusting the playback control to zero sets the the recording level (and my headphone level) down to zero. ('ll leave WASAPI/Stereo Mix testing to you). So there does seem to be some change within Audacity. Perhaps Steve can shed some light on this?

I also noticed that in 2.4.2 that both Audacity controls fed back to Windows and changed the Windows playback volume controls, but in 3.1.3 the Audacity playback volume control seems to have mostly no effect. (Curiously, increasing or decreasing this control by any amount will increase the Windows volume by 2 points. In 3.2 Beta, neither control currently seems to do anything in this situation).

Personally, I prefer the 3.1.3 behavior as when I’m recording I prefer to have the levels unaltered - I can always change them later with the Amplify effect or with the envelope tool.

Thanks jademan - interesting results.

With WASAPI as host:
Online source volume affects recording level, but only insofar as reducing the existing relatively low level down to nothing.
For Stereo Mix, neither recording nor playback volume affects recoding level.
For Speaker loopback, recording volume does affect recording level, but only per source volume as above, though these adjustments do not interact.
There seems to be no way of raising the recording level beyond the sub-optimal state that exists when eveything is set at 100% / 1.0.
Has no-one else encountered this issue on W10 using 3.1.3?

Just a brief commment regarding MME and Stereo Mix.
With both playback and recording volume set to max, my phones are loud, but the recording level doesn’t get close to 0; it peaks at around -6, so no clipping occurs.