Weird Audio Issue

Hi all,

I'm working on a 7 minute piece that is Motion intensive. A lot of back and forth.

Yesterday, my audio (in FCP) started acting strange. Sometimes the left channel will play in slow motion, but the right channel will playback correctly. Sometimes the other way around. Sometimes both channels will go in slowmo. Video plays back correctly, and then after a few seconds (basically, at the next audio cut) FCP will realize something is wrong and tell me I'm dropping frames.

I initially had all the media on an external 500GB hard drive with about 350GB free. I moved it to the system drive (120GB with about 20GB free) and the same problem occurs.

I have trashed my FCP prefs twice. Re-started several times. Banged my head against the wall a few times, just for good measure. None of these things seems to help.

This project is supposed to be ready in the morning.

Help?

-MW

How many tracks of audio do you have? Video too.

Michael Horton
-------------------

Dump your render files with Render Manager and then re-render the audio (with Audio Mixdown) and see if anything changes. If not, try taking everything offline (SHIFT-D, Leave Files on Disk) and then reconnect. If that doesn't work either, start a new sequence with matching settings and copy everything over. A new project file, if you have to.


www.derekmok.com

I'm finding a similar thing on a bunch of imacs running FCE. It's just one line of Apple intermediate 108050i, with six lines of audio, and almost every time we're getting crackling with a slow motion start, then it resolves and plays correctly. In this case I think it's that the machines just don't have the grunt to cope with the work and the network and it's adjusting the framerate so that it can play correctly. I haven't had time to do any experiments yet, but I will be today.

What happens when you make a self contained movie of a short section for output? Does the .mov have the slowing problem?

Ok, tried all that, nothing seems to work. Blew out my render files and re-rendered, it's still happening.

Jude, I exported a self-contained version and it still happens. Slowmo audio in one ear, regular in the other. The VU meters (in FCP) read the same way.

Grrr.

Update:

The music I was sent is 44khz, the voiceover is 44khz, the hdv audio I shot is 48khz, and the sequence is 48khz. Let's see if a little standardization will fix this problem.

Also, try setting your RT to safe, quality to a lower setting, and frame rate to full. I did this this morning and it helped a lot with the FCE systems.

It's still happening, and the only way that seems to fix it is trashing render files and re-rendering. Even trashing the audio render files and doing a fresh mixdown doesn't fix it. Ugh.

-MW

When I have had audio problems in the past-
trashing FCP user preferences has fixed it-
this was not on FCE or Imac tho--Jay--

I don't think the preferences are the problem in my case, since this is 22 imacs, and they all show the same problem. I think it's just lack of grunt, which was pretty much proven by lowering the RT expectations.