Audio tracks delayed

[MiximusMaximus]

This is an odd one so I thought I would hit the collective knowledge here to see if anyone else has seen this issue.

I open a session to start mixing and everything is fine. After some time I notice that the bass and key parts are out starting to slide backward in time. To get everything back to normal, I go into the buffer size and change it from 1024 to 528 and back again, and it snaps things back...for a while.

The particulars of my set up are PT 2018.1 running on a MAC 5,1 12 core (3.46 processors) 128 gigs of RAM. The computer is interfacing via Lynx AES cards to a Mackie dxb. Everything is clocked to an Apogee Rosetta 200, files are 44.1k/24 bit.

I have had this setup for a bit and done quite a bit of work on this rig and this seems like a rather recent issue to pop up. Anyone else experience this oddity?

[albee1952]

Hmmm, 2 things come to my mind:
1-is your version of Pro Tools compatible with your version of OSX?
2-have you trashed prefs yet(always worth a try for odd behavior)?

[MiximusMaximus]

I am running High Sierra 10.13.6 which is compatible, I neglected to mention that in the initial post. I have not tried trashing the preferences yet. I guess that is where I will go next. Thanks for the suggestion.

[Ben Jenssen]

I presume delay compensation is enabled?

[MiximusMaximus]

Yes, delay comp is on. Nothing is showing red. It's all very odd.