phantom clicks

Audacity 2.2.1 Windows 10, using a Behringer Xenyx Q802USB mixer and xm8500 dynamic microphone:
I am getting an occasional click that does not appear to be part of the displayed envelope. I hear it but no click shows in the waveform. How is it being introduced into the audio? How can I remove it? See attached wav file. The clicks happen at about 0.70 seconds.

Actually, the clicks show up very clearly in the spectrogram track view:

and they show up in the normal waveform view if you zoom in close enough (see the sudden “step” in the waveform):

The other problem that I see is that your recording level is too high, causing some of the waveform peaks to be clipped off:

The clipping problem is the easiest to resolve - you just need to reduce the level on the Xenyx Q802USB.

The “clicks” may be more difficult, because there are many reasons why this can occur. The problem is basically that the digital signal has lost some data (“skipping”), causing a discontinuity in the waveform. The first thing I would try, is setting the Audacity default sample rate to 44100 in “Edit menu > Preferences > Quality”, then restart Audacity and make a new test recording.

If the skipping problem still occurs, look at this page in the Frequently Asked Questions for some other possibilities:

[EDIT] - Steve beat me to it…

It looks like a [u]dropout[/u]. If you upgrade to the current version (2.3.0) it will tell you if you have dropouts or not.

That’s usually caused by some application/process/driver “hogging” your system for a few milliseconds too long, your recording buffer isn’t’ read in time, and the buffer “overflows” and you get a glitch.

I hear it but no click shows in the waveform.

I see something “funny” when I zoom-in… The hard part is finding it. Zoom-in to the approximate problem area, then click the drop-down arrow to the left of the waveform and select Spectrogram. Where you see a “funny looking” area, select and zoom-in again. Then go back to the regular waveform view.

…. Unrelated, but you’ve also got a lot of [u]clipping[/u] which means your levels are too high. If it was clipped during recording, you need to turn-down your recording levels. It’s OK if your recording levels are a little low… You can amplify after recording. But, you can’t fix clipping.

I am aware of the clipping problem and I am correcting that. About the “glitching”, it was much worse at 44100. If its a processor overload issue I should try to limit the processor workload? What is the best way to do that? The Intel processor is an i5. Should it really have these issues?

An i5 should be able to handle recording, even large multi-track projects, without problems. However, if there is any kind of data bottleneck anywhere in the system, it can cause this type of problem, even on a high end system.

Two of the most common causes:

  1. Windows is trying to do an update.
    Solution: Force a Windows update, and repeat as necessary until there are no more updates available.

  2. Anti-virus / security software is interfering with Audacity.
    i) Ensure that all of your security software is fully updated, then reboot the computer, and wait until the computer is fully booted. Then retest Audacity.
    ii) If there is still a problem, temporarily disconnect from the Internet, and temporarily shut down your anti-virus / security software ane retest.
    iii) If step (ii) fixed the problem, find out how to white-list Audacity and “.au” files, or replace your security software with something that is less intrusive.