HDX PT 2018 CPU Spikes AAE -9171 Halts Playback

[Howardk]

I am having problems putting this system into production. . . been working on it for bout a week w/ no luck so far with errors causing Pro Tools to stop playback.

In one simple test session, I have one stereo audio file routed to 16 stereo Auxes, and one Interface connected, with a 128 sample buffer and 44k1 sr. I am getting CPU spikes of up to 40%. . . won't run for even a second with 64 sample buffer. I have tried with either just a single Aurora Lynx or a Single 192 I/o with same results. Tried different Digilink cables. I have remove All plugins from the folder, Trashed Prefs etc. . . Unused Network interfaces are Off, Wifi off, Blue Tooth off, created a new Admin Login (with minimal things going on), enabled Trim. . . no appreciable differences from any of this. I did go thru the Avid Optimization notes and I think I did everything suggested . . . maybe I missed something?

Interestingly, if I take the same session and change the Playback Engine from HDX to Built-In Outputs, the CPU Total meter stays at 4% and solid, no spikes.

I am coming from a 7 card HD Accel system on PT 10, which has been mostly solid (other than elastic time crashes and poor Virt Inst performance) and very powerful for mixing and was low latency for tracking. . . I am trying to move to newer Po Tools for 64 bit, so I can run newer VIs, and also for features such as Freeze/Commit. I have a couple projects that I need to get started on right away. . .

As soon as I start using some Virtual instruments or other AAX Native plugins, I start to get AAE -9171 halts with a 128 sample buffer. Hard to work at tracking with the system as it is performing at present. . . basically light sessions will not run without the AAE -9171 freeze frequently occurring due to CPU Spikes . . .

Hoping this is solvable. . . Ideas/Suggestions?


System Outline:
Pro Tools 2018-12 on Mac Pro 2010 2.93GHz 12 Core 48GB, ATI Radeon HD 5770
Sierra 10.12.6, 1 HDX Card, Lynx Aurora 16 x 2, 192 i/o x 2
System Disk: OWC Mercury EXTREME Pro 6G SSD
Session: Samsung SSD 850 EVO 500GB
Also tried Mac Pro 2010 2.66GHz