Mastering Plugin causes tracks to shift

[Brightbelt]

Hello,
I'm on an iMac Pro 2017 -Catalina 10.15.6 - on Pro Tools 2020.5.

I have a project in which I want to put a mastering plugin on the DrumBuss.
I have done this before with no issues. Now, however, doing so causes all the other tracks to shift time-wise so that the rhythm plays back out of sync. You can actually witness the whole window shifting slightly out of sync.

I've had issues before with putting plugins on the Master Buss while recording, but I have cleared the Master Buss out here so that it has no plugins on this project as yet. Both the Delay Compensation and Low Latency Monitoring are active.

I appreciate any assistance. Thanks for your help,
Frank B.

[Darryl Ramm]

What plugin... might help.

You are using a UAD interface? So is this a UAD plugins in Pro Tools? Something like the Ampex mastering plugin with huge internal latency?

You should do some math here. How many samples is this being shifted? What's the plugin latency expected? What is delay comp showing for the latency? Numbers and colors all OK? How do those numbers change as the plugin is enabled/disabled? It's possible for a plugin to report the wrong latency, but that's very rare. And you may just have a weird routing problem or a corrupt session.

We can't see your routing or what is going on. But you can play with a simple version of what you are doing and in a new session and try to see what is happening... including turning latency comp on and off. Adding/removing that plugin etc.

UAD software/plugins all up to date? Tried trashing prefs?

[TOM@METRO]

What is the mastering plugin?

Are you attempting to monitor thru the plugin while recording, or is this just on playback after recording without it?

When you say project, are you recording to the cloud, or is this a session?

[Brightbelt]

Thanks for your replies. Let me clarify your questions.....

I have a Lynx Aurora 16 channel acting as master, clocked with an Apollo Thunderbolt UAD2.

My iMac pro has 18 cores and 256 GB of Ram - Also, I have a DSP accelerator for the UAD plugins. I am pretty much cruising as far as firepower.

Several Plugins cause this - the main one is the Waves Abby Road Mastering (Stereo) Plugin, but other Wave mastering plugins will cause it and other mastering plugins (Like Elysia the UAD version) cause it.

Also, this isn't a latency issue. This causes ALL the other actual physical tracks to shift in time so that they are out of sync. You can SEE the tracks actually shift position right when you insert the plugin.

Right when you remove the plugin, the tracks actually shift back into sync.

Also this is not a recording issue either. I am simply inserting a plugin during the mix phase.

I hope this helps. Many Thanks for helping,
Frank B.

[Darryl Ramm]

Originally Posted by Brightbelt

Thanks for your replies. Let me clarify your questions.....

I have a Lynx Aurora 16 channel acting as master, clocked with an Apollo Thunderbolt UAD2.

My iMac pro has 18 cores and 256 GB of Ram - Also, I have a DSP accelerator for the UAD plugins. I am pretty much cruising as far as firepower.

Several Plugins cause this - the main one is the Waves Abby Road Mastering (Stereo) Plugin, but other Wave mastering plugins will cause it and other mastering plugins (Like Elysia the UAD version) cause it.

Also, this isn't a latency issue. This causes ALL the other actual physical tracks to shift in time so that they are out of sync. You can SEE the tracks actually shift position right when you insert the plugin.

That *is* a latency issue, it's latency compensation doing it's thing. Latency comp moves the all the faster things to line up with the thing you are making slow by bunging a big old fat high latency mastering plugin on... it's all latency compensation can do, it can't move things forward in time. Causality and time travel, and all that. Things just don't shift around because they are bored. Stick enough high latency stuff in there and you might well exceed Pro Tools ability to compensate... so you working out the numbers here is important.

Again, I would work out what is happening with latency, and what you expect to happen. What's the spec for latency for that plugin? What shift are you seeing? https://www.waves.com/support/tech-specs/plugin-latency What are the latency comp numbers showing, colors?