Why does mic input not sustain over a longer period of time while making a constant sound using the new Audio Capture Component?

I’ve set up the Audio Capture component using the new audio engine in UE 4.20 and am printing out the results of the mic input amplitude. Everything works perfectly, except if I make a long and continuous sound the amplitude drops after a period of 1 or 2 seconds down to its default value. I then have to stop making a sound and start again for the correct amplitude to show up but it drops down every time. It seems as if there is some sort of time limit on a continuous sound.

Why does this happen? Is there a setting in the C++ script I can change or anything else I can do about this?

Hey man, we saw this with some mic input hardware too. When we used a logitech mic input typically used for VOIP, it dropped. When used a professional mic, it was fine. We concluded it was a weird hardware/firmware thing for VOIP mics (probably to reduce continuous background noise during VOIP sessions). I agree it sucks.

If you are using a real microphone and still getting this, then it would be different from what we experienced, but the culprit would be in the back-end lib we’re using for mic capture (RtAudio). The RtAudio Home Page

However, I’ve perused the source and found nothing doing anything like artificially reducing output. So I’m 95% sure it’s the mic’s themselves doing this.

Hey! Thanks for your reply, and yeah that does suck. So I’ve been testing on HTC Vive using the inbuilt Vive microphone, and also on my ASUS ROG Zephyrus laptop, and it happens on both.

I’m going to see if I can get my hands on a professional mic, but from what you’ve written it seems as if there’s no workaround if I had to continue using the Vive mic? I’m using the input amplitude to trigger interactivity in the environment so it’s quite jarring when it suddenly drops.

Happy to hear the wildest/most random solutions :slight_smile: