ilkosl

Second data point for you — and unfortunately it's another Combi. I have a 2026 Octavia IV Combi 2.0 TDI 150 (facelift). Same thing: - Booming/droning starts around 140 km/h and gets louder with speed. At 160 it's noticeably louder but it's the same tone — the pitch never changes. - Shift to neutral and coast: engine drops to ~1000 rpm, the drone carries on completely unchanged. So nothing to do with revs or the drivetrain. - Fuel level makes no difference. I thought at one point it only did it with a full tank, but I retested properly and that was a red herring. I can't answer your hatch/liftback question, but at least you now have a second Combi with an identical signature, on a different model year and in a different country. One more thing that might be relevant. Separately from the drone, my fuel pump is clearly audible at idle — louder than the engine — but only when ambient temperature is above about 25 °C. Below that it's silent. Same 25 °C threshold you're describing for the drone. Might be coincidence, might not. That temperature threshold is what I keep coming back to. The thing on these cars that changes state right around there is the active radiator grille shutter. It stays shut at speed when there's no cooling demand, and opens once it's hot and the A/C is working. Open shutters at 150 km/h means flow into the engine bay and a cavity that can resonate at a fixed frequency. It would fit everything you've described: front-ish location, headwind makes it worse, drafting behind another car kills it, nothing below 25 °C, and it appearing after a few months rather than from new. A few questions so we can look for a common part: 1. When you removed the roof bars, did you take off the longitudinal rails themselves, or just the crossbars? The rails sit in a channel with end caps and those are worth taping over. 2. Panoramic roof? Tow bar? Wheel size? 3. Have you had a look at the grille shutter position via VCDS or ODIS while driving? If it reads open exactly when the drone is there, that's most of the answer. 4. Has the dealer actually driven it with you, and did anything come back from a TPI search? I'll record mine and run an FFT so we can compare — if I land on 129 Hz too, that's a very strong argument to take to Škoda. Two documented cases in two countries is a lot harder to wave away than one.