Hi all, i have a strange "problem" i own a 54 plate A3 2.0L TDI Sport, whenever i down shift from 6th to 5th or up from 4th to 5th, as i release the clutch i get a small "whine" noise, it only happens going into 5th gear. When i was at the Audi garage getting some parts i asked about it and the parts guy got one of their mechanics and he hadn't heard of the issue before and thought it was odd it only happens going into 5th, he suggested it is not something to worry about, that maybe the sync is slightly out but he would expect it to happen in all gears. He said it may be worth changing the gearbox oil to see if that helps and also look in the oil to see if any metal is inside and that would then be a problem. I was going to change the gearbox oil myself but from what i have seen online (very little) i need a special suction pump to remove the oil? I thought it would be possible to drain the gearbox oil in the same way you do for the engine oil? Any advice on how to change gearbox oil myself or if you have experienced the problem and know what it may be would be very gratefully received.