Problem, random noise. [RESOLVED]

Lucy_k_p · Post by **Lucy_k_p** » February 16th, 2009, 9:30 am

I am recording using Audacity 1.2.6.

Sometimes, for apparently no reason a loud crackling takes the place of my recording. It has happened multiple times, usually around one minute after I start recording.

This isn't background noise, it completely drowns out whatever I had recorded and the entire track becomes filled with blue.

There's nothing in my environment that could be causing this, I only find out when I go back to listen to my track and find that my recording cuts out and a loud roaring begins. This roaring continues until I stop recording.

Any ideas?

Edit: Here's a sample of the noise: http://upload.librivox.org/share/uploads/xx/randomnoise.mp3

RuthieG · Post by **RuthieG** » February 16th, 2009, 9:52 am

Ouch. Just an idea, but check that you haven't accidentally slid the - ____ + slider in the label (at the left of the track) across to the +.

EDIT:

Tell me if that doesn't even make any kind of sense, and I will post a screenshot.

Ruth

Lucy_k_p · Post by **Lucy_k_p** » February 16th, 2009, 10:12 am

I don't think so. It doesn't appear to be in that position, and the noise will happen even when Audacity is minimised and I'm scrolling down a word document.

RuthieG · Post by **RuthieG** » February 16th, 2009, 10:22 am

Have you tried uninstalling and reinstalling Audacity? (But I haven't come across that particular horrible noise before - someone else may have a better idea.)

icyjumbo · Post by **icyjumbo** » February 16th, 2009, 10:38 am

A couple of hardware things to try out:

1. Are all the connections secure, nothing wobbly, or not fully pressed into its socket?

2. Could your microphone have got some moisture on its pickup? They don't like moisture at all, which is why they are supplied with a silica gel packet, to absorb excess moisture in the atmosphere around them.

harvey · Post by **harvey** » February 16th, 2009, 2:26 pm

Lucy_k_p, try these:

Audacity (1.2.6) (if you haven't already done this)

Edit [menu] > Preferences ... > Audio I/O [tab] >
Playback, Recording [both sections] >
Device: (select your specific input and output devices)

The default setting for both "Devices" (assuming you have MS
Windows) is "Microsoft Sound Mapper ...". You are changing this
default to something else, something specific to your system.

For "Playback", there probably is only one other choice (the name of
your sound card or sound chip set): select it.

For "Recording", the same should be true if you're using a non-USB mic
(only two choices): again, select the one with the name of your sound
card / chip set. However, if you do have a USB mic, then there should
be a third option naming your mic: pick it.

Additional, illustrated instructions (steps 4 and 5) (this link is in
the LibriVox guide Audacity 1-2-3).

According to my on-line research, this fixed, for a different program,
the same loud hissing noise you are getting, which behaved just like
you describe. [= fingers crossed =]
Wifi

If you use WiFi (wireless) Internet connectivity to your PC, try
turning it off. WiFi sometimes causes interference with audio recording.

Lucy_k_p · Post by **Lucy_k_p** » February 16th, 2009, 3:03 pm

Mic is in securely and my settings are correct. I will try disabling my Wifi and see if the noise still occurs.

Lucy_k_p · Post by **Lucy_k_p** » February 16th, 2009, 3:53 pm

Even with Wifi off the noise still occurs. To test I just set Audacity to record then read a word document. I really don't know what can be doing this.

RuthieG · Post by **RuthieG** » February 16th, 2009, 3:55 pm

This happened suddenly, presumably? Your initial test was fine. You don't have any different programs running now, do you?

Ruth

harvey · Post by **harvey** » February 16th, 2009, 4:11 pm

[harumpfff!]

Ruth asks a good question: Was there a time when you could record
without the hiss, or have you been plagued with it since you started?

Let's see what happens when you record from a source other than
your mic, so unplug it. This will help us figure out if the problem is in
the computer or the mic. I recorded from another program (Winamp)
playing a music file; you might choose a LibriVox audio book. You
could also play an audio CD in your PC.

On Audacity's mixer tool bar (to the right of the slider for recording
volume), there is a pull-down menu for selecting the recording source
(the default seems to be "Microphone"). If you play a music file,
select "Stereo Mix". Or, if you play a CD, select "CD Player".

Now record while your source is playing. You should see the same
things going on as when your mic is the source. Record for however
long you did with the mic when the hiss started. Do this recording
several times.

Something else to try, although I'll be surprised if this fixes the
problem. I've read that it's a good idea to mute microphone playback
if you don't need to hear what the mic is picking up, or if no mic is
plugged in. Yes, this will prevent you from hearing your voice through
the speakers as you're recording, but, no, it won't interfere with the
recording process.

In Windows Volume Control, check "Mute" under "Microphone"
(illustrated instructions).

Lucy_k_p · Post by **Lucy_k_p** » February 16th, 2009, 4:34 pm

I just uninstalled Audacity, restarted my computer, reinstalled Audacity, disabled wireless and let Audacity record dead air while no other programs were running. The noise still happened. I wasn't even touching the computer. I'd really like to know what's causing this. I'm going to try downloading Audacity from a different location, but other than that I'm stumped.

Lucy_k_p · Post by **Lucy_k_p** » February 16th, 2009, 4:59 pm

Okay I've unplugged the mic. I don't seem to be able to set it to record from Winamp or CDs though.

However I do have a built in mic which I am recording through. I'm not sure this mic was ever completely deactivated, or if it's even possible for me to do that. Could some sort of interaction between them be causing this? Although if it were, I'd expect the interruption to be constant, rather than appearing intermittently.

This didn't happen in my test, but I recorded for less than one minute at a stretch there and this error appears randomly, but usually takes at least one minute to show up.

14 minutes in and built in mic still hasn't gone wrong.

So it probably is my microphone - which is in fact a logitech USB webcam with built in mic but it's all I have. There is a loud level of background buzz when I use it as well.

However I can't use the built in mic to record because it is just too quiet. It is positioned at the top of the screen so I can't move it closer to me and still read stuff off the screen, and in a sensible position my voice sounds as though it is coming from miles away underwater, even with mic input volume on full.

It's been a while since I've used the Webcam Mic, but I did use it to talk to my family about a year ago, and there were never any problems with our conversations. I also recorded a lot of poetry for my own private use 2 years and never noticed a problem. But I now remember that I've never used it on this Laptop. I think I may have to buy a new mic...

Lucy_k_p · Post by **Lucy_k_p** » February 16th, 2009, 5:02 pm

Also I already have hearing my voice through the speakers switched off in Audacity, I find it distracting.

Lucy_k_p · Post by **Lucy_k_p** » February 16th, 2009, 5:42 pm

I'm pretty sure now it's a mic issue. I'll test that completely tomorrow by webcamming with someone with it and seeing if the same noise appears.

I've ordered a new (but very cheap) mic from Ebay, hopefully I'll be able to record something decent sounding with that, and it won't take too long to arrive.

Thanks for everyone's suggestions.

harvey · Post by **harvey** » February 16th, 2009, 6:05 pm

Odd that you couldn't record from another source, since I did exactly
that in troubleshooting your problem.

Yes, it would appear that what you've got is an interaction between
conflicting components.

It's possible that whatever you do in Audacity to switch off hearing
your voice through the speakers while recording is not the same as
muting the microphone playback in Volume Control. Therefore, muting
it would be worth a try.

Above in this thread, I mentioned the other program which has had
hissing problem like yours. It is Skype, where this problem seems
to have annoyed a number of people. For some, it was related to using
a Web cam with mic for video calls. Some folks were able to solve the
problem by updating to the latest drivers. Others by the configuration
procedure you said you'd already done.

You might be able to disable the internal mic through the Device
Manager. Control Panel > System > Hardware [tab] > Device Manager
[button]. In the Device Manager window, click the + sign to the left
of "Sound, video and game controller". In the sub-list which is
displayed, there should be an entry for the internal mic. If so,
double click on it to open its Properties dialog. At the bottom of
the General tab, there is a pull-down menu under "Device usage:".
Change that to "Do not use this device (disable)".