Hi everyone! Since my english is very bad i made the AI wrote this post for me, but those are my real findings after hours of trials and errors, hope this helps!

I wanted to report an issue I was experiencing with my Fanatec Gran Turismo DD Pro in F1 25, which I have now been able to reproduce and solve.

After updating the GT DD Pro to the latest firmware with FullForce support, I started experiencing extremely violent left/right oscillations of the wheel at higher speeds when driving.

The strange part was that the problem was session-dependent:

• The first session after starting F1 25 was completely normal.
• When starting a second race/session, the FFB would suddenly become unstable.
• At higher speeds, the wheel would violently oscillate left and right on its own, making the car practically undriveable and causing crashes under braking.
• Pausing the game and power-cycling the DD Pro (OFF → ON) would immediately fix the problem.
• However, the problem would return again when starting another session.

I initially suspected an F1 25 issue, especially because this started around the time of the latest game update.

I tried several settings on both fanatec app and F1 game, but none of these provided a satisfactory solution.

The important finding

I downgraded the DD Pro firmware to the last pre-FullForce firmware, available in the v1.4.2.3 Fanatec app Installer:

• GT DD Pro Base: 1.8.0.6
• GT DD Pro Motor: 1.0.3.2

I then tested F1 25 again under the same conditions.

The problem is completely gone.

I tested multiple consecutive sessions without power-cycling the wheelbase, and the violent oscillation did not return.

This makes me strongly suspect that there is a firmware/FFB state-management issue affecting the GT DD Pro with the newer FullForce firmware, rather than this being purely an F1 25 setup issue.

For anyone experiencing the same problem, the pre-FullForce firmware is therefore worth testing.

Obviously, downgrading means losing FullForce functionality, but in my case the difference is dramatic: the DD Pro is completely stable again in F1 25.

I hope this helps other GT DD Pro users who are experiencing the same issue, and hopefully Fanatec can investigate what changed between the pre-FullForce firmware and the current firmware.

System:

• Fanatec GT DD Pro
• F1 25 (PC, using EA App)
• Latest F1 25 update
• RTX 5080 / Ryzen 9 9950X3D

If anyone from Fanatec needs additional information or testing, I would be happy to provide it.