Sudden screeching Audio with headphones on

Hey All,

I called apple on this one and they have no idea what to tell me. I experience this problem most of the time on my Mac at work and at home but with less frequency.

I'll be editing and suddenly the audio screeches to an a deafening decibel level and blows my ears off. All audio becomes unintelligible and the only sounds is this nails on chalk board blow out. It freaking hurts and usually steam is still coming out of my ears afterwords.

This seems to happen randomly. I thought that it was happening when I use audio transitions to fade out different tracks, and if there were to many things fading at the same time. But now it is happening with a single audio track on top of a stereo music track. All music files are AIFF. Already trashed FCP prefs.

I've experienced this with the audio playback going through built in output and built in line output. (I'm on a Mac Pro at work, 2 x 2.8 GHX Quad core Intel Xeon 10GB Memory. )

Like I said, I called apple on this one but they act like they have never heard of this problem before. (And I experience this same problem on my MBP 2.26 GHz.)

Has anyone else experienced this? Could FX plug ins have something to do with this? I use the FX Factory Pro plugins package. Could this cause the problem?

Hey I am glad that you posted this issue. I have had the same exact experience at least three times in the last 5 months or so. It is very strange and I just turned my audio board off really quickly to get rid of the noise.

It happens at random points and in different projects. One of the times I happened to be looking right at the audio meeter in FCP and I noticed that all the levels jumped to the top.

I wonder if this has happened to others?

Do y'all use Skype or other conferencing software? Do you have SoundFlower installed so you can record internet audio?

Either or both of those can cause serious audio instability.

Koz

I have a vague memory of a post about this a year or two ago, and it happening to me, and a cause (and solution) being discovered. Isn't that handy? I did a form search for "audio screech" and got only one hit that wasn't it. Not sure how else to search. Does that tickle anyone's memory?

Scott

<<<One of the times I happened to be looking right at the audio meeter in FCP and I noticed that all the levels jumped to the top. >>>

So you have a sample of the sound?

Koz

<<<I'll be editing and suddenly the audio screeches to an a deafening decibel level >>>

And how do you make it stop?

<<<It is very strange and I just turned my audio board off really quickly to get rid of the noise. >>>

So in your case you have an external sound mixer and the problem goes away when you pull down the fader controls? Or turn the board off? Does it come back when you bring the faders back up?

<<<I did a form search for "audio screech" and got only one hit that wasn't it.>>>

Go out to Google and let Google send you back in. Nobody is going to give forum search software any awards.

Can either of you make it worse -- happen more often? I really need to know about SoundFlower and Skype. Both of those establish custom sound pathways outside of Final Cut that can get you into serious trouble.

Koz

My first bet would be on audio render files. Do the screeches happen at the same spot every time? What happens if you change the audio level of the clip(s) in question, or disable the clip and re-enable, or dump render files?


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Koz

Interesting idea, but the fact the original post talks about screeching in the headphones and a responder talked about having to turn his audio board off makes me doubt the UPS reason. That and my hazy memory of my own experience with it. There was something to reset....

I'm just throwing ideas on the wall.

Something inside FCP struggling to get out because the meters move with the problem....

Koz

Quote

Something inside FCP struggling to get out

Jeez, thanks for really creepifyin' my morning, Koz.

I wish I had something constructive to add here, but I've never heard of a problem like this, and I don't really know from audio. You could come back and tell me that you needed to rub your power cables down with WD-40 to make the electrons flow more smoothly, and I couldn't argue with you.

I'm having a little flashback - something about resetting your Easy Setup.

While we're at it, what version of FCP, QT and OS?

Scott

<<<Jeez, thanks for really creepifyin' my morning, Koz.>>>

Colorful and dramatic metaphors are us. No extra charge.

The English version of that is that it's unlikely that machine itself is doing something wrong because the Final Cut volume meters go nuts. That means FCP internal sound services
"know" about the problem.

We go a long way over on the sound forums by having the poster supply a bit of the bad sound, but that's gong to be rough here.

Koz

Sorry, been away from the computer for a couple days.

Do y'all use Skype or other conferencing software? Do you have SoundFlower installed so you can record internet audio?

No and No.

<<<I'll be editing and suddenly the audio screeches to an a deafening decibel level >>>

And how do you make it stop?

Hit Space Bar

My first bet would be on audio render files. Do the screeches happen at the same spot every time?

In some cases it has been a bad audio render. I reconnect and it will fix the problem when it happens on the same spot. But this same type of screech can occur randomly as well.

what version of FCP, QT and OS?
7.1, 10, 10.6.2

Thanks for all your questions. I'd love to figure this out.

Closer. So you have to be playing a track for this to happen. Spacebar stops playback. You don't stop the machine and go freshen up your hot tea and it's screaming when you get back.

Koz

Does it change? Do you get one scream only and it's always the same beginning to end. Does it build up or squeak or start slowly?

Does it do it if you scrub over the offending clip?

<<<In some cases it has been a bad audio render.>>>

Trust me I know what I'm asking, but the next time you get one of these that you can stop and start, can you plug your machine Line-Out (or headphone out) into the Line-In of your MacBook and record some of it?

You can use QuickTime Pro, Garage Band (I've never done this one) or the free Audacity audio editor.

This is the audio equivalent of a picture is worth a thousand words.

Koz

Yes, I have to be playing a track for this to happen. It never just starts on its own. I don't know if I will be able to get an audio recording of this. Mostly happens at work on the Mac Pro through headphones. I'll see if the opportunity presents itself and then I'll keep you posted.

Let's narrow this down a little. My experience with this was on earlier versions of FCP, QT and OS than you have, but that may mean nothing. You talk about headphones, but can you confirm whether you also can hear it out of the built-in speaker without the headphones?

Just to humor me, go to Easy Setup and reset it - select a different setup, save it, then go back and select the right setup. Seriously, I think this is what we did a year or two ago to "fix" this, no telling why.

Scott

Scott, so far so good. I did what you mentioned about changing the easy setup, then changing back. That seems to have taken care of the problem. It has not happened in two days so things are looking good.