CPU spikes Pro Tools 2018.7

[Nick Namnone]

Running Pro Tools 2018.7 on MacBook Pro 15" Proc. 3.1 Ghz, 16GB ram
High Sierra 10.13.4

I have just started getting CPU spikes that are causing my recordings to have crackle or distortion on them. I had replaced an Apollo 16 with a Symphony MKll 32x32 when I started getting errors. I tried going back to the Apollo 16 but the problem continues.
If I run at low hard ware buffer the problem is worse. I even get CPU spikes just sitting in input. At the longest possible buffer time the Apollo seemed stable for about 7 minutes. In my CPU usage window in Pro Tools I can see the meter spike and go red.
This is only recently started to happen. I have been using the Apollo this way for a couple of years. I ran it with 2018.7 a few times and it worked. It is likely coincidence but the problem started after I installed the Symphony software. I also used an RME Babyface the day before I started having issues. I have uninstalled the Symphony software but that hasn't helped. I looked to see if I could install Sierra but it doesn't come up when I reboot in recovery mode. Any one else having and issue like this? Any suggestions? My next step will be uninstall and reinstall Pro Tools

[tclash]

From what I have read 10.13.4 is really bad for CPU spikes.

I just started using 2018.10 on 10.13.6 and it's working well although I haven't done much recording, mostly mixing.

Some people are fine on 10.13.6 and others are still having problems.

[Nick Namnone]

thanks. It just cropped up. It had been working fine. Cropped up after I installed Symphony software. could be coincidence.

[Nick Namnone]

Embarrassing but the issue was easily solved. At some point I must have turned on the Ignore Errors (may cause clicks) in the playback engine. Since it is normally off I just didn't see it was on. I was adjusting HW buffer and never looked any further.