rubbing on 306 1.6

Have started to notice a rather strange rubbing noise in my 306 1.6. It started origionally when the clutch was pushed in, and when the accelerator was at the biting point. It only realy happens with the accelerator in 4th and 5th, but the noise persists when the clutch is pressed whenever the car is moving. Origianally, it seemed to happen when the car had been on a long journey, and fairly rarely at that, but it seems to be happening all the time now. I'm not sure what the hell is up with it and the performance is still the same, but it is driving me up the wall, especially as i'm not sure if I am doing any damage to the car! Can anybody help? Thanks. Tom D