Crackling Audio Through TDM Bus

[Ray Campbell]

In my case I am currently running only internal ATA drives and off internal clock in the 192 I/O. And the static (sometimes) continues after stopping playback. This seems to rule out SCSI voodoo, clocking issues or drive speed respectively.

It sounded at first like it could be a clocking issue, and I have my DAT machine connected, so I made sure that digital I/O to/from the DAT was disconnected in case it was somehow injecting some sort of digital signal.

ADC has been rolling around my brain for a while as a possibility, thinking the system is trying to shift audio back and forth in time to compensate.

It remains to be seen if turning off ADC will cure it for me. I'll report back after I've done some more work on this session.

For others, trying disabling ADC to see if that helps.

Ray

[PTUser NYC]

And the static (sometimes) continues after stopping playback. This seems to rule out SCSI voodoo, clocking issues or drive speed respectively.

The system is ALWAYS clocking. When you're not playing anything, there are still a whole bunh of zeros running around, getting added to other zeros, and making a bunch of new zeros. If the clocking on that is wonky, you'll hear crackles.

[Ray Campbell]

Well, I did a reasonably full day of tracking yesterday, and did not notice a single "snap", "crackle" or "pop" (tm)

I think, in this case anyway, that it has something to do with Automatic Delay Compensation. I'm surprised if there is a bug (sshhhh ), that more folks have not experienced it.

When I get some time, I will go through each plugin to ensure it is up to date and supports ADC. Also, I'll try turning ADC back on to see if the crackles resume.

Is it feasible that plugins that are not "ADC-aware" may cause this problem?

I would have thought that those plugs would just revert to the manual offset technique...


Ray

[Ray Campbell]

Well, I was working happily yesterday without having any crackling so, for an experiment, I thought I'd turn ADC back on.

I had the System Usage window open, and selected "Short Delay ADC". I watched as it closed my session to change the setting, then re-opened.

I watched the system usage as it went to just the HD engine chips being used. As the session re-opened, each chip was activated with plugins. As each chip indicator lit up, I heard crackling through the monitors. When I hit "PLAY" the crackling was back.

I de-instantiated every plugin in the session, and the crackling went away.

So I'm pretty certain this is an ADC issue with older plugins.

My PT system is still OS-9, so Digi won't update my plugins until I buy PT 6.4+. So every time I take my iLok to a work on a PT 6 system, I have to disable ADC. I might as well stay home...

Ray

[Bo Walker]

This is happening to me as well. HD3/PT6.4cs8 + cs6Plug-In updater. (Whatever is the latest) Using 192's clock.

I'm in an 88.2 session. Drums (stereo pair) bussed to Aux Stereo with Compressorbank2, Phoenix and Analog Channel. I have a bus going from Aux channel to Altiverb on sep Aux. ADC is on. (Long Delay)

When there is a stereo drum roll (ie panned across) all sorts of crackling etc. Snare and kick don't seem to crackle.

Toggle off ADC - no crackling. Back on again crackling. This is an intermittent problem however.

Done usual - trash prefs, DIGIsetup etc etc. Permissions, Reset-OF, FSCK etc.

One thing I have done is updated to 10.3.5 however. Mostly its been fine and as others are experiencing this in different OS I don't think its that.

I use internal SATA drive so its not a SCSI issue.