Crackling sound when recording and also upon playback

Hello everyone,
I am getting a bad crackling sound when I am recording and hear it upon playback at exactly the same points. I have an HP Elitebook laptop and Windows 10, and am using Audacity 2.4.2. Over the months that I have had Audacity I have had minor crackles or individual cracks, but in the last month or two the problem has gotten far worse. I use a StarTech external USB soundcard, and, aside from the crackles, the sound is great. Before I got the soundcard, I went from my mixer to the built-in microphone input on my laptop for recording purposes. I don’t believe I have had anything like the consistent crackling problem I am now experiencing. I just read a post from 2014 about a similar crackling problem, and Steve’s advice to the gentleman who asked for help seemed to resolve the issue. The advice was to turn off the Software Playthrough function. Generally, for months I have not had it on, and, instead, monitored myself though my mixer while recording. So, I felt hopeful that by turning off the Software Playthrough function, my problem would disappear. But the crackling has continued. One strange thing I just noticed today regarding the crackling sound is that it happens at very regular intervals-they tend to occur every 2 minutes and 20-30 seconds! In between these times, the recording is generally very clear and basically sounds good. Whether I try to record a mic or guitar from my mixer to the external USB soundcard/laptop or record a cassette tape from my Sony dual cassette player/recorder to the soundcard/laptop, I am running into this same crackling problem. However, when I play the cassettes through my mixer and monitor it directly from the mixer itself, or sing through a mic into the mixer and monitor it through the mixer, or play a guitar through the mixer and monitor it directly through the mixer, there is essentially no problem. I can’t figure this out, and it is preventing me from doing all my audio work. If anyone can help me to solve this problem, I would be very grateful.
Dan (4DanQuestt)

You are probably getting [u]dropouts[/u]. Dropouts are related to multitasking and interrupts. If some application/driver/process “hogs” the system for a few milliseconds too long, you get buffer overflow and a glitch in your audio.

Try to minimize the applications and background operations that are running and you can try increasing the [u]Buffer Length[/u].

Many thanks, DVDdoug. That is all good to know. I did have a problem one time in the last couple of months or so when parts of a recording/tracks were apparently lost, and I recall getting a special window/alert pop up (which I don’t think I ever received prior to that) saying that some of the audio was lost, etc. I don’t believe it has come on since then, but I have had the crackling problem getting worse lately. If this crackling problem is indicative of “dropouts”, wouldn’t I be getting the dropout window popping up to inform me of it? I tried recording some cassette tapes today to see if I could identify the source of the crackling, and I never got any dropout window or alert. And, after reading your response to my original post, I checked my recording preferences settings to see if the dropouts detection setting was on, and it was. So I’m a little confused about that.
Also, your advice to minimize my use of apps etc. while recording sounds good. I will try doing that tomorrow when I have more time to experiment. And, if I change the buffer length, should I first try going up from, let’s say, 100 ms to 110 ms, or move it up more incrementally, such as 101 ms or 102 ms?
Thanks again,

if I change the buffer length, should I first try going up from, let’s say, 100 ms to 110 ms, or move it up more incrementally, such as 101 ms or 102 ms?

I’d try doubling it. Normally, the only downside to a bigger buffer is more latency (delay) but latency doesn’t matter at all unless you are singing/playing and the delay in your headphones makes it difficult to perform.

…In some cases reducing the buffer size improves things but that shouldn’t happen and I don’t know why.

Some people solve problems by temporarily turning-off Wi-Fi or their anti-virus.

Thanks for the extra information, DVDdoug. At least I have more things to try now, and, hopefully, something will work. I’ll keep you posted.


Hi again everyone,

I have tried all of the things that you advised me to look into, DVDdoug, but, unfortunately, I am still getting crackling sounds when recording and playing back. There may have been a little improvement, but the essential trouble persists. Is there anything else I might try or consider?



Increasing the CPU-priority of Audacity from “Normal” to “Above Normal” (& no higher).

Thanks Trebor. I’ll try that immediately, and let you know how it turns out.


Hi everyone,

I just increased the cpu-priority for Audacity from normal to above normal, as Trebor suggested, and there seems to be no change. I’m still getting the crackling sounds. Does anyone have any other ideas of what might be behind this weird problem?



Possible other solutions …
Turning off Wi-Fi, (i.e. airplane mode),
whitelisting Audacity with your antivirus,
ensuring you have elbow-room on your hard-drive.
defragging your hard-drive

[Plan-B: Audacity’s competitor … ].

This thread is similar to another:

I like Trebor’s plan B solution…

Before you do that, it may be worthwhile checking that all of the sample rates are the same. The easiest thing to check is to simply switch Audacity’s sample rate between 44100 and 48000 and see if that fixes the issue.

What you are looking for here is for the hardware rate to match that on Windows to match that in Audacity. To check the Windows sample rate, in the Windows search bar, type “mmsys.cpl”, then Recording > startech usb > Properties > Advanced > Default Rate.

Hi everyone,

I’ve continued to try the different things that have been suggested, and, although I haven’t finished with this yet, I have made some more useful observations regarding the problem. Firstly, I am not getting the crackling problem when I record (my mixer, guitars, mics, etc) through my laptop’s built-in microphone jack. When I first got Audacity months ago, I had no external USB soundcard, so, temporarily, I just used this mic jack. In general, the signal isn’t quite as good as that coming through the external USB soundcard, but it is still pretty good. So, the crackling problem seems to be linked to my use of the external USB soundcard for recording purposes (but, when I just play music from Youtube, Windows Media Player, etc, there is no crackling, unless, of course, I am playing back something that I recorded through the external USB soundcard).

Regarding jademan’s suggestion that I check the sampling rates of both Audacity and my external USB soundcard via windows (i.e. by typing in mmsys.cpl, etc), the sampling rates on both Audacity and the soundcard (for line-in recording-which is how I’ve been getting the crackling) is 44100 Hz. However, the sample format is different for each. Audacity’s default sample format is set at 32-bit float, whereas my external USB soundcard is set for 16 bit.

My two questions are:

(1) Should I change Audacity’s default sample format from 32 to 16, so that it is the same as that of my external USB soundcard?;

(2) Does the extra info. I have provided here on the crackling ONLY happening while recording through the line input of my external USB soundcard (and NOT while recording through the laptop’s built-in microphone jack) help any of you to narrow down the cause (and possible solution) of this crackling problem?

Many thanks,


Good question. We are just concerned here with the bit rate/speed (Hz) only.

Well, you’ve got your thinking cap on…

In virtually all cases it’s best to leave that at “32-bit float”.

Thanks again for the input. I won’t change the default sample format. I’ll just leave that at 32-bit float. Regarding the issue of the crackling only happening while recording through the external USB soundcard, I have ruled out that the soundcard itself is defective, because I have two of that model, brand new, and I have tried them both and have had exactly the same result (unless they’re BOTH defective, which is unlikely). So, I would be tempted to think that it is likely that that particular model/brand is incompatible with my set-up, except for the fact that, when I first began using that model, I had no crackling problem. Otherwise, it would surely narrow down the cause of the difficulty, but this recent change would suggest that it is something else. And, unfortunately, I cannot think of anything that occurred recently that might account for it. So, I might just be limited to recording through the laptop’s built-in mic jack. Too bad, because, except for that one interfering sound, I get pretty good quality.

Thanks anyway,


You didn’t say, have you tried downloading updated drivers for these sound cards ?

That’s a great question, jademan. I hadn’t given a lot of thought to that, but that certainly could be the problem. As I said earlier, I bought two of the exact same model from Startech very recently (within the last two months or so), and I don’t know how often something like this needs to be updated. But I’ll get right on that tomorrow, and try and get everything checked out and up to date. Thanks for the suggestion!