Not a solution, but possible pointers to consider
Could it be that at the end of the straight t4 Brno, your inputs were somehow more than the wheel to windoze to game interface combined with the effects coming back game to windoze to wheel could handle? Have you made changes to how often the wheel inputs are updated, I dont know much about it but I know buried somewhere are all sorts of settings for wheel update rate, even FFB prediction of what it expects your next input to be. I know on lower spec machines just generating the FFB over rumble strips can cause lag that many think is graphics lag but I view more as a combination of the loads in the machine caused by it having to calculate the physics, generate the graphics and the feedback of a car that's bouncing over a rumble strip - in a similar way people complain of and point the finger at graphics lag when sometimes its the game trying to keep up with them having the car sliding and 'out of shape' - t4 Brno is one of those easy to have the car on the verge of crossed up, kind of, but not kind of bends , could you have found a way of entering it under lots of on off suspension, steering, FFB,throttle, clutch and brake inputs/outputs that led to the downchange somehow been missed?
FFB can in some instances (usually when it stops altogether) be reset while in game/ontrack by hitting ALT + F , unrelated I know but useful to bear in mind before a reboot.
I'm Mr positive this week, so I prefer to think 60 people viewed the thread in the hope of helping, but didn't post because its such a strange one that they didn't know (same as I don't) how to silver it, but credit due to them for looking in the hope they could help - much better than viewing them as SAD for not posting.. like I said tho I'm on a posi-drive this week !
I hope you solve it, let us know if you do - if you don't stay positive and hope the problem never comes back again; the G27 is a great wheel !
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