Hi folks, car is a 3.5 year old fiesta st,

For the last month and steadily got louder, i first thought it was a wheel bearing noise but they've all been checked and are fine

After a few mins when the car is up to temp, when i accelarate it makes the noise of a bearing/wind, and also when i let off the throttle the noise is louder
Sitting at 70 it just drones away and is quite annoying

When i press the clutch the noise disappears, however if i press the clutch and touch the throttle, the noise happens. If i am stationary in nuetral and press the throttle it happens again

I will have to eventually put it to a garage but i do not fancy being shafted by them claiming it's something big when it maybe is not

I've tried to be as accurate as i can but its a weird noise
Gears can be sticky after a thrash too, which has just happened recently aswell

thanks