Recording desktop audio very quietly

Hi, I’m using v3.75. I’ve used earlier versions many times to record desktop audio etc but now I can’t seem to get it to work

In audio settings, I set the Host to Windows WASAPI and in recording settings I set it to Speakers (USB sound device)(loopback)

However when I record I only get a very quiet recording and a waveform which is so narrow it’s barely visible.

Recording level and playback level are already at 100%

what am I doing wrong? I used to be able to adjust the audio input to fill the waveform window but I can’t find anyway to do that now

I’m using windows10 in case that matters