My mouse is a M535 — I’ve googled this problem I’ve downloaded utilities that claim to fix it but nothing works --its awful - the stuttering and lag while trying to pan just drives me bonkers.
Note: I’m using it on a 2018 mac mini on Big SUR
I prefer not to use a apple magic mouse that trackpad as i like something with physical buttons/ scroll wheel
i see a lot of grumbling online about logitech and apple compatibility so im not sure what to do??
please recommend another vendor to try
My M535 has been working normally until the 11.5.2 update. I thought that was the reason for my sudden problem. I hope someone has a solution for you - and me.
Yes, same problem here. A week ago I went from Mojave to Big Sur and my Logitech M235 started acting up. After a couple of hours I switched the mouse of my work laptop with the Logitech and all was fine. The Dell mouse works fine under Big Sur and there are totally no problems with the M235 under Windows. Both are wireless.
I guess not a real solution, because there is nothing wrong with the mouse itself.
Also Bluetooth is a mess now, the iMac finds reasons to connect to my EarPods when I listen to audio on my iPhone. I tried removing the EarPods from my Mac, but because of iCloud syncing they keep coming back.
Is this what you own?
Yes, that’s the one.
My MX Vertical is connected by bluetooth and I don’t appear to have any issues. When you say pan, what do you mean?
I used to run in to issues with Logitech devices when Time Machine would start running, even non bluetooth, but now I don’t run TM, I’ve not run in to any issues.
My M235 is not connected by Bluetooth, it uses an USB receiver.
And when I had Logitech devices connected via the USB reciever, I had issues as well, but only when Time Machine spun up to start work backing up. Since I found that out and disabled Time Machine, I’ve had no issues via bluetooth or the USB reciever.
I’ve the same mouse (M235) that I use on my MBA whilst traveling and don’t have issues either. I don’t have any Logitech software installed.
move the mouse across the screen left to right
it won’t scroll smoothly
I don’t have time machine active - my mouse doesn’t user a receiver
i do have a USB hub connected – i will disconnect it to see if that does anything to stop the lag and stuttering with scrolling and panning
its perplexing but i’ll order that Dell mouse and hope the issue is fixed
Same general issue though - RF interference. That Logitech dongle is basically a proprietary Bluetooth type receiver, using a very similar frequency range.
I have everything hard-wired now due to my USB hard drives interfering with Bluetooth signal. I would imagine the issue could be generalized to USB peripherals, probably particularly those that draw significant power through the port.
I was able to get some better signal at one point by plugging an extension cable into the Mac and moving the receiver away from it. Basically having the dongle not be right next to the USB ports. But that’s silly to have to do.
Does other stuff work okay via Bluetooth? If not, then it’s probably RF. If so, then it’s an issue with the Logitech specifically.
wow removing the USB hub seemed to fix the problem
ordered an anker hub hopefully that will place nice on the mac mini
Hope this thread can help someone in the future - can’t believe i didn’t figure this out sooner lol
Presumably the USB hub lives somewhere a bit away from the Mac Mini. What happens if you plug the receiver into the hub instead of the Mini?
My logitech mouse doesn’t use a receiver
i think it was the cheap USB hub that was messing with my HW – I’ll know when this anker gets here if the problem returns but at least i know worst case when I’m editing video Ill just unplug the hub for smooth mouse scrolling
Ah, Bluetooth. So it does effectively use a receiver, but you can’t move it because it’s built in. 
I have my Magic Trackpad wired via a lightning cable because of the same problem you describe. ANY external hard drive plugged into the back ports on my Mac Mini causes the Bluetooth signal to go wonky, and the trackpad has all sorts of problems.
I really hope switching the hub solves your problem. That said, this interference issue is a known thing and there’s some discussion of mitigation strategies here:
https://discussions.apple.com/thread/250480034
Might be worth a read in case that’s your problem - no need to replace a hub if the problem is something else.