@George D fwiw, I've been working through what sounds like a similar problem. I've always built my own PCs and am very comfortable with all aspects of fine tuning for audio performance. My current cfg had been running flawlessly for years but starting "acting up" around Mar 2021. This particular project was an older one that a client wanted to revisit and used to run just fine with absolutely no problems.
The symptom was a serious degradation/smearing of sound quality on playback, like running the audio through a meat grinder (or putting your thumb on the reel for a tape machine). It would only happen for 10-30 secs and then somehow "recover'. Not sure how this compares to your "clicks and pops" but the performance monitor would go crazy when this happened, super erratic, cores jumping/spiking all over the place. This would also happen when opening a VST or the browser (i.e. to open a user manual, not to check on sports scores...) something that -never- used to happen. The project isn't super large, only a drum VST and a few amp sims in addition to std audio tracks with FX. I don't generally freeze these as I've never had to before SO... not thinking the project/VSTs itself is the problem. Additionally, the ability to run at low latency has been significantly compromised. Used to track just fine on the very same project down to 64 samples. Then only way I could get reasonable playback now was to raise it to 512, which is pretty useless for tracking.
The major areas of focus were;
1. WIN 10 updates
- Running WIN 10 Pro with updates disabled except for security updates. Always an issue, but I've got a good checklist and always managed to restore the changed settings quickly and easily when they happened, which was not often. Decided to update to the latest version (last update was over a year ago) to solve the problem.
= Didn't help.
2. VST updates
? Possibly some update to an existing VST?
- Couldn't pin it down on any in the project. They're all by reputable proven devs and run fine in other projects (and DAWs) with no issues reported for any of them.
= no obvious suspects
3. Other SW updates (like other applications phoning home)
- rechecked / reinstalled the native A/I drivers (they were always the latest update, but...)
- I've added some new VSTs/suppliers with various means of authorization. Tried freezing those and disabling any service that looked like it might be trying to do something.
- tried running the project completely off-line (Internet disconnected, actually boot cfg is off-line, have to manually go online)
= no improvement
4. Checked my system services again. Ran Latency Mon and for the first time on this system, it would show some issue when running the project but w/o much of a clue as to a specific cause. The highest DPC counts were for the Kernel Mode Driver Framework Runtime. The second highest were for LatMon iteself... Multiple sessions were rather uneven and hard to pin down. FYI, no BT, WiFi, etc, active, only Window Defender running for when online, never been a problem in the past.
? Not sure where to go with this, still looking into it with no idea what changed, so the challenge is to hunt down what might have made it worse.
5. CxB changes/updates.
- CxB has never been the problem (despite the number of outraged posters in this forum 🙂), but there have been a -lot- of changes and had me considering the possibility of some newer potential stability issues. Not that I have any insight into the development, but it is a very feature rich (=complex) program.
NB This project has since crashed several times and flagged an issue with Cakewalk core. Doesn't mean it wasn't caused by some VST issue, but despite the best efforts of the Support team (they've been super responsive), no clear cause has been noted.
> Worked through a matrix of Record/Playback IO buffer sizes, A/I buffer sizes and was able to confirm a few settings which helped, but mostly raising the A/I buffer. Changing the Record/Playback IO buffer sizes generally made it worse.
= All changes were correlated with Performance Monitor specs during playback but they generally behaved as expected...
> Tried various settings in the Initialization file.
= Back to the original settings as none of the changes made much sense and generally only made things worse.
In the course of working through this, it's started to behave a bit better, which makes it sound like a moving target, or maybe it just takes a few reboots for everything to settle down? I still have a problem project with repeatable symptoms at a specific spot in the playback, trying different states/cfgs to see what might expose the culprit. And also noting the issues are only with older projects so far (like 3-5 years old) being opened in this years version of CxB. FWIW, all of my newer projects are running fine atm, so I'm considering the possibility of some project specific corruption or as yet undiscovered backwards compatibility issue?
Don't know that this does you any good but just hearing about something similar might help. I don't expect to find any answers here as I'm assuming it's something specific to my system, but stuff like this comes with the territory (infinite cfg possibilities + ongoing dev) I'll come back if something useful gets figured out.