Camera movement with LMB or RMB cutting out at random

[Breakbeat]

Open up MS Paint or your favorite similar program. Start drawing a line (hold down mouse button and drag.) Does the line ever stop drawing?

Visit this page: https://openprocessing.org/sketch/186320/ Click in the box 100 times. Does the box register 100 clicks?

Do you have another mouse you can try?

The symptoms you describe are those of a dying microswitch that won't hold a click. My expertise on this comes from the dozens of mice I have thrown in a closet somewhere, collected over the years, that have bad or failing switches. And, in my experience, well-known and trusted brands don't really last any longer than an Amazon basics mouse. I've got several of each in that pile I mentioned.

The problem is even more confusing because dying microswitches often fail intermittently. It might not lose a click for a half hour, then lose ten in a row.

The easiest way to eliminate the hardware as an issue is to try a different mouse. Even a cheap-o five dollar mouse would demonstrate whether or not the issue lies with your current hardware.

Good luck.

Edit: I notice now you said, "multiple different mice"; you might want to try those mice on MS paint and the click-counter as well. Or if you have only been trying wired mice, try a different USB port, or try a wireless mouse if possible.