[Darryl Ramm]

Thanks for all the details!

Make sure you have all those systems optimizations done exactly right. But yes you just left off a few things like moving out plugins in your initial post which is a not uncommon cause of issues like this, and frequently overlooked so kinda natural to assume you might have missed that.

At some point you have to give up and just try a clean windows and Pro Tools install... which you already did, so good thinking there. But make absolutely sure you got all the low level optimization correct.

Can you post a SiSoft Sandra report. A long shot but that _might_ show up suspects.

When you've done all this type of careful troubleshooting, take a break and go back and recheck stuff, maybe recheck the out of left field stuff.

Also confirm that the clicks are really coming from Pro Tools, not say introduce in monitor controllers, monitors, not caused by RF interference etc. Yes even if other apps don't seem to produce these clicks, try to think of some way this might be possible. Check though stuff looking for anything crazy. Things as crazy as hidden tracks with clicks on them, I've seen open mics driving through hardware monitoring system (not Pro Tools) producing noises folks swore were coming from the DAW. It is possible to get caught by something totally unexpected.

Go hunting for any apps or utilities that might have the same interface open.

It might be worth trying another new clean install of Windows 10. Install just Pro Tools and the interface driver, absolutely nothing else, just on a spare test drive or volume.