Weird digital distortion while recording

[Musepro]

Hello all!

While recording, I sometimes get this weird digital ringing/distortion that creeps into the track and overruns it. The only thing that fixes it is quitting/restarting ProTools and the track is still ruined. All of the other tracks sound fine, so playback is not affected, only tracks in record.

Here is a link to an MP3 example of it happening while working out a bass part tonight: http://www.filedropper.com/recordglitch

I am running a 1st gen Intel MacPro with the latest supported OS, PT 10 updated and an M-Audio Profire Lightbridge, clocked from a Lucid GenX192 which is also sending clock to MyTek converters. This system has been rock solid for years. This recording glitch started happening once in a while about a year or so ago, but it's happening more frequently in the past month even though nothing has changed!

Can anyone help? Thanks!

[T3chNik4]

What are you using as your soundcard (audio device) to record?

[Craig F]

when is the last time you blow the dust out of them?
heat is the enemy of timing circuits

[Musepro]

Originally Posted by T3chNik4

What are you using as your soundcard (audio device) to record?

The M-Audio Profire Lightbridge.

[Musepro]

Originally Posted by Craig F

when is the last time you blow the dust out of them?
heat is the enemy of timing circuits

Regularly. My studio is very clean.

[TheProFool]

That used to happen on a windows based system of mine, as well as a mac one. It usually had to do with running different system preferences sound output than the one in my DAW. Would that apply in this situation?

[Musepro]

Originally Posted by TheProFool

That used to happen on a windows based system of mine, as well as a mac one. It usually had to do with running different system preferences sound output than the one in my DAW. Would that apply in this situation?

Your comment gave me some encouragement and so I tried switching my system preference outputs to all of the options (such as Firewire device, Protools Aggregate and Core Audio), each running for a session, but the problem still persists. Thank you for trying though!

Just boggles my mind as to why the system was perfect until a year or so ago. The Mac OS is the same that's been running for years, as is the M-Audio driver. ProTools is the only thing that's been updated, so I am guessing it has something to do with that.

[fmilian]

Did you load a session that had the sample rate on external ? like spdif, word clock, something?
Maybe the sound card is set to extenal clock and it's still looking for locking up to some signal that doesn't exist.
I don't know your sound card, but some cards, even if they are going to internal (having no external digital signal to lock on), still search for locking on digital input.
Just an idea..

[Musepro]

Originally Posted by fmilian

Did you load a session that had the sample rate on external ? like spdif, word clock, something?
Maybe the sound card is set to extenal clock and it's still looking for locking up to some signal that doesn't exist.
I don't know your sound card, but some cards, even if they are going to internal (having no external digital signal to lock on), still search for locking on digital input.
Just an idea..

The interface driver software is set to external and the interface it's self has a light that flashes when no clock is present and stays lit when it has clock. It stays locked to the GenX192 and both the driver software and the interface show that as confirmed. If it were a clocking issue, I think you would hear the typical mismatched clock sound all the time. My issue is perfect sound for a while, then this crazy noise out of nowhere after about 30 minutes or so. My clocking has not changed since this issue started.

[fmilian]

I had a M-Audio Audiophile 2496 that had that problem. And it was about the external clock. I found that when I bought the second Audiophile, and link them together. There was no more random noise.
It's internal clock chip is wasted. And I don't know why it didn't manage to stay on extenal clock. As I said, the only way it did work, was having two cards.
I sold the one that was fine, and the other one had a trip to the garbage...