I have no idea, how this is possible in an operating system this sophisticated, but it certainly happened here. I can only imagine that the mouse I used (Logitech G203) ****s up system I/O so bad, that any other task running concurrently is forced to yield to these very I/O computations. Replaced the mouse and everything's running buttery smooth.

So, he plugged in my mouse gets *exactly* the same issue. My roommate incidentally also uses a MacBook running Big Sur, and never had a similar issue as described. The mouse works fine during low workloads on the Mac and other PCs in general, by the way. Somehow, I started suspecting the mouse itself. So, faced with the real possibility of having to re-install MacOS, I tried out some of the most unlikely things I could.

So, I tried every step they've instructed me to do (Reset the SMC, an so on.) but nothing really worked.

It's been some time, but I've now contacted apple support because it's really started bothering me a lot. Can anybody recommend a hub that you know works well with a usb wireless mouse receiver? Is this the fault of the RCA usb c hub I'm using? Is it a fault of the computer? I want to try a different hub but I'm seeing some reviews complaining about this same issue with usb wireless mouse receivers, on a bunch of different hubs, not to mention they are all unknown engrish brand companies. If I plug the USB mouse receiver into its own USB C port (using another adapter) it works perfectly every time, but it's annoying having to take up a whole usb c port just for a mouse, when I have other things I want to have plugged in at the same time. Right now everything is plugged into the hub and it's working great, but it's likely i'll have to rearrange everything again after letting the computer go to sleep. It's not consistent which ports work, sometimes it works one way, then I come back later and have to change ports again to get it to work. But it usually stops happening if I either switch the usb receiver to a different port on the hub, or move the hub to a different usb c port on the computer. The cursor will stop moving every few seconds. Sometimes, the mouse is very laggy, to the point of being unusable. I'm using an RCA usb c hub on my 2019 16' macbook pro to connect an HDMI monitor, usb keyboard and a usb wireless mouse receiver.

Usb receiver for logitech mouse mac