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So for the past few days, my keyboard and mouse have been very laggy sometimes, and unresponsive for a few seconds. For example my mouse would be a lot slower as its lagging when i move it, if that makes any sense, apologies if it doesnt. anyone have any advice?
Not sure what K & M you have but sounds like a driver issue. Maybe...
For drivers Driver Booster from IOBit.com works fairly well in finding out of date drivers. Free version is better than most paid for software lol. Their driver library is massive and usually up to date.
Hardware itself might be having issues as well. If you can borrow or use another mouse and keyboard do that first and see if problem persists. If so delete and reinstall the game itself. If none of that works, your problem could be something else more severe.
Do in this order: K & M swap>game reinstall>use driver booster. Updating drivers is always risky, so its recommended to that that last.