[Eric Seaberg]

We've been fighting this for about 10-days. Running Mojave 10.14.6 and Ultimate 2019.6 on an iMac Pro, 2.5GHz Xeon W with 64GB RAM. Connected to 1.2PB SAN via 10GB Ethernet SMB share, but that doesn't make any difference as it doesn't work with local SSD, either.

We've got the Native card in a Sonnet 3 (Thunderbolt-3) chassis, but even trying to run a session using built-in audio and the chassis disconnected made no difference.

We startup ProTools and without any session loaded, the System Usage spikes the CPU at 100% and doesn't change. Nothing plays, nothing loads!

All background apps, i.e. Spotlight, etc., have been disabled which still makes no difference.

If the session will play, within seconds we get an error stating there's too much CPU usage by the host processor, yet Activity Monitor shows nothing running except ProTools. BTW, the session size makes no difference whatsoever... it could be a single track VO or something with 60+ tracks and crazy plug-ins.

Finally today we decided to back rev to 2019.5 after deleting all prefs and settings... and we're back to normal.

If anyone, including Avid, has something for us to try that we haven't, I'm more than happy to do so and give you a report.

For the time being, we're able to work on the older version.