Recording problem

[annemarie]

I am trying to record from an old (not digital) camcorder.

I am using Windows XP on a laptop with a fairly decent audio card and most recent drivers. I have a cable from audio-out (camcorder) to microphone input jack using line-in. Everything works great for about 2 minutes, then the whole thing goes and stays all jumbled (out of synch??).

The original audio is still on and works fine -- so it's not a source issue.

I have used Audiocity before and have not encountered this problem.

Any suggestions?

Thanks
Anne-Marie

[kozikowski]

<<<I have a cable from audio-out (camcorder) to microphone input jack using line-in.>>>

Or, more properly, you have a cable going to the Line-In connection instead of the Mic-In connection. Yes. That's perfectly correct. Camcorders usually produce a "line" level signal.

As to why it stops now and it didn't used to, are you filling up a hard drive somewhere? Video and Audio captures accumulate large files very rapidly if you're used to saving an Excel spreadsheet or a Word document. Do a properties for the drives connected to your system and see how full they are. Shouldn't go much over 90% full on any drive in a production machine.

When was the last time you checked and defragmented your drives? If you used your machine normally for a long time before this, I bet your drives are full of partial and segmented files and documents. It's not broken, that's just how hard drives work--but they slow down when they do this and audio (and video) production demands clean fast hard drives.

If all that is in order, I'm going to start asking about virus software.

Koz

[annemarie]

Ok....I have defraged....and have 28.27GB (53%) free space.

I have tried recording the audio again and have the same problem.

My virus protector is AVG 7.5 free version.

What can I do next?

[kozikowski]

<<<My virus protector is AVG 7.5 free version.>>>

Sometimes, virus protection can cause problems like this. Try, as a very temporary measure, disconnecting your internet, disable AVG, and try the capture again.

<<<goes and stays all jumbled (out of synch??). >>>

Is there any way for you to post a small segment of the show just before through just after the distortion? Ten second sound file? The forum won't let you do that, but do you have a web page or community file posting service? Sometimes by listening, I can diagnose the problem very rapidly.

Sometimes not.

Koz

[annemarie]

Hello again,

I uploaded a fragment to http://www.montserrat-caribbean-villas.com/wav.html

Thanks for the help.

Anne-Marie

[steve]

Ooh that's nasty.
I can produce something similar if I reduce the audio buffers down to about 10 milliseconds, but it doesn't start off normal and then go bad, it starts off bad and stays bad. It may still be worth checking the audio buffer settings - you will find them in "Edit -> Preferences -> Audio I/O". The default is 100ms, which should be ok for most set-ups.

I don't think that AVG will be the problem - AVG is very light on resources and I have it switched on while I use Audacity without any problem and it not as if my Pentium 500 is a fast machine

Does the "interference" start at the same place each time (ie after 120 seconds) or does it vary?

Could there be some background process that kicks in periodically that is causing the problem? For example, an e-mail program checking for new mail, AVG starting a system scan, a program checking the web for updates, a hard disk manager deciding to start defraging or something like that?

[kozikowski]

<<<for about 2 minutes, then the whole thing goes and stays all jumbled (out of synch??). >>>

I ripped your sound clip apart and I can tell you that the above isn't true. The clip is always distorted and it get vastly worse at two minutes. I put much chocolate on a bad sound card or digitizer.

You may have selected 16 bits for your capture process, but I don't think you got them. Further, at two minutes, I think you lose more and more until right at the end, the sound clip is trying to proceed with two or three bits. Not enough to do anything even remotely like natural sound.

I'm struggling to think of a way to describe this... Even "normal," your system will not preserve quiet sounds. The digital numbers necessary for double pianissimo violins are simply missing.

The conversion from analog audio to digital bitstream is by far the most likely place to get this effect.

I can get compulsive and post pictures of how I know this and what I was inspecting if you need it.

Koz

[kozikowski]

Wait a minute. You're on a PC. Open Windows Sound Recorder and see if that works any better.

Windows Sound Recorder
Start -> Programs -> Accessories -> Entertainment

Koz

[steve]

Wait a minute. You're on a PC. Open Windows Sound Recorder and see if that works any better.

Sorry to say that's a non-starter - Windows Sound Recorder only allows you to record 60 seconds at a time.
(annemarie said that the problem occurred after 2 minutes of recording)

[kozikowski]

Another direction.

Rereading the first post. Most PC laptops only have microphone level inputs. I'm assuming from your slightly odd sentence that you have all three audio connections on your laptop; Line-In, Mic-In, and Headphone-Out (or Line-Out).

Is that correct?

Or do you only have the usual two; Mic-In and Headphone-Out. If that's the case, then you are feeding a line level audio signal from the camcorder into a microphone level input, a voltage overload of about 1000 to 1. I wouldn't be shocked to learn that the arrangement worked for about a minute or two and then the poor laptop threw in the towel and failed.

Koz