G500 wheel problem

Hello.
I have serious problem with my mouse wheel.When i scroll, from time to time, it doesnt jump/duck at all..it happens pretty often,like 1/10 times.This literally destroys any of my runs, regardless how much effort i put into.The strange thing about this, while geeking a map for example, it occurs mostly on the same spot(jump).every run its like 80% chance to fail there.And i can feel it comes, almost everytime i get this feeling,it skips next jump and poof, i can try again..

I have it like 1,5 year for now and im not sure its hw or sw problem.I dont remember if this was occuring when it was new, but certainly not that often.I also tried to refund/replace it in store, but they told me its ok..ofc it is since they cant test it while playing cs.

Im so worried about that because i love kz but this issue drags me down.If wouldnt been for this, g500 would be perfect mouse for me.

I have got logitech flowscroll and setpoint installed.

So do you guys have any similar problems or suggestions how to fix it?

Thanks for your feedback.