My 2004 Honda Civic 1.6SE suffers intermittently from a disturbing oscillation which seems to suddenly build up from low intensity to a noise which fills the cabin making conversation and concentration extremely difficult. It first started 15 months ago on the M42 and I thought it was due somehow to surface conditions. We were doing 50 to 60 mph at the time and reducing the speed to about 45 mph seemed to cure the problem and during our visit to the Bromsgrove area we had no further problems. It does not appear to affect the performance of the vehicle. We had similar instances during a visit to Scotland last September and on our way home through the Borders but speeding up above 60 mph seemed to take the vibration away. On our return home we experienced no further problems on trips until we had the same trouble but now even as low as 30 to 40 mph but again returning by motorway at higher speeds, no problem. The noise appears to start somewhere in the front off-side and I have discovered that slight pressure on the brake pedal makes it disappear only to reappear as soon as I release it. It has been regularly serviced by Honda dealers, the last occasion late January on schedule where the disc wear was estimated at 30%.