PT Native HD 11.1.2 doesn't compensate for plugin delay changes while recording

[CHD]

Recently discovered this with a shock while printing a mixed 51 minute episode. Pro tools Native HD 11.1.2 dynamically compensates for plugin delay changes while in Input monitor mode, but does not while recording. For example, take two audio tracks (i.e.dialog source tracks) and bus them to the same recording audio track (stem). Insert identical plugins on both source tracks. The plugins should be something, which plugin processing delay DEPENDS ON AUTOMATABLE PLUGIN PARAMETERS. I noticed this phenomena with Fabfilter Pro DS that has three switchable parameters (split band, look ahead, oversampling), which influence the plugin delay. But any Linear Phase enabled EQ like DMG Audio Equality will do. While the stem track is in Input monitor mode, change the plugin parameters on one of the tracks and watch the reported delays in the mix window update accordingly. The sound from source tracks remains in sync. Now start recording. At the moment Pro Tools drops into recording, the delays in the mix window freeze at the values, reported just at the recording start moment. The further changes of delays are not displayed and are not compensated accordingly. The sound from the source tracks gets out of sync. The recording track is set to auto latency off, but this phenomena occurs with the auto latency on as well. My current system is Mac Book Pro late 2013 2.6GHz 16GB 1TB, Mavericks, Pro Tools HD 11.1.2, Metric Halo ULN-8 with the latest drivers. My current workaround is to set and forget any plugin parameters that affect plugin delay.

[tom_lowe]

Good to know, luckily I don't automate different "modes" such as Oversampling or anything or the phase-type in EQuality so guessing this isn't an issue?

Is there any reason to automate between these modes?

[CHD]

Not so much necessary to automate different phase modes of EQs. One can get caught with this only when instantiating a plugin and later on starting tweaking it. But with the Deesser wide band/split band modes it's not quite obvious. The strangest thing is that everything is compensated very well when mixing until you drop into recording the mix

[tom_lowe]

Originally Posted by CHD

Not so much necessary to automate different phase modes of EQs. One can get caught with this only when instantiating a plugin and later on starting tweaking it. But with the Deesser wide band/split band modes it's not quite obvious. The strangest thing is that everything is compensated very well when mixing until you drop into recording the mix

So when recording, a plug-in's delay is calculated when you hit record? as long as no parameters that change this are automated, then all is OK?

[CHD]

Yes, exactly.

[mhuang]

I just got nailed by this bug in pro tools 12.4 with equality, frustrating to say the least!

[Frank Kruse]

Beware of automating any parameters that change the delay. This can and will cause clicks. I would vote for such parameters to not be automatable.

See here:

http://duc.avid.com/showthread.php?t=376875

Especially FabFilter plugs are dangerous.

But it's not a bug it's actually a feature that causes big problems. I have written to FabFilter and they said they would remove delay changing parameters entirely from automatable lanes in the future.

Frank.

[mhuang]

Originally Posted by Frank Kruse

Beware of automating any parameters that change the delay. This can and will cause clicks. I would vote for such parameters to not be automatable.

See here:

http://duc.avid.com/showthread.php?t=376875

Especially FabFilter plugs are dangerous.

But it's not a bug it's actually a feature that causes big problems. I have written to FabFilter and they said they would remove delay changing parameters entirely from automatable lanes in the future.

Frank.

Frank, in my case, I didn't automate any parameter in Equality that cause a delay com change, I simply initialized Equality in Linear phase mode and automated some EQ moves.