noise floor too quiet

For some reason since upgrading to Audacity 2.4.2 files that passed ACX check before are now being flagged as having a noise floor that is too quiet? I’ve never had this problem before, but when I bought a new computer and then uploaded the newest Audacity version first of all the ACX check didn’t come automatically with the download and I had to download it separately. It also now looks completely different and gave me different results on some files. If a noise floor is too quiet what does one do?

Could add-in very-faint comfort noise.
But preferably find out what is causing the problem,
(possibly a noise-gate is being applied before the sound gets to Audacity).

Bear in mind the Audacity ACX tool can give spurious values for the noise-floor if the selected audio contains less than half a second of room tone, (also will give a misleading result if the audio contains more than half a second of true silence, e.g. if a noise gate has been used).

It also now looks completely different and gave me different results on some files.

ACX Check Classic had trouble with longer sound files in the newer Audacity. The current ACX Check only presents the three readings that ACX is watching for, is speedy, and, for the most part, produces readings nearly identical to Classic. They do work a little differently, and on difficult files can give different readings. Please note you also have to pass the ACX Robot which works in a similar way and ACX Human Quality Control when that’s done.

being flagged as having a noise floor that is too quiet?

A suspiciously quiet background noise (-80s and -90s) usually means your computer is helping you with voice processing. ACX doesn’t always like that and it can cause a submission to fail for “Overprocessing.”

Windows PCs come out of the box all set up for Skype, Zoom, Chat, Conferencing, and Voice Transmission. Not high quality theatrical recording. The complaint is usually talking-into-a-milk-jug, honky sound in addition to switched, oddly quiet background. This processing is needed so the six people in your Zoom don’t all contribute refrigerator noises and air conditioning whine at the same time. It’s similar to the processing on your phone.

You are the poster child for this because you started a sentence with “I have a new computer and…”

Look down the machine’s setups for “Windows Enhancements,” and turn them off for theatrical reading. This can be harder than you think because Skype and Zoom will try to turn them back on next time they run. It’s also possible they won’t let you turn them off. Make sure Audacity and your show are the only things running when you record.

If there is any question about the machine, you can Clean Start Windows 10 by Shift+Shutdown > OK > Wait > Then Start. Windows will drop all its hidden settings and start over.


Note that it is a “warning” and not an “error”.

ACX do not publish a minimum noise floor level, but they do specify that they expect natural “room tone” and not dead silence. The warning indicates that the plug-in found at least half a second of dead silence (or very close to dead silence).

You need to work out what you did to achieve dead silence, then stop doing that.