2004 A3 FSI Noisy Fan

I had some problems with fans on my old A3 and have recently got another A3 and would you believe it but think I may be having the same problem after fixing the old one LOL

The problem this time is that the main large fan is really noisy when it kicks in, sounds like an aeroplane taxing down a runway, is this a common problem and does it mean the fan is on its way out? The problem I had with the old A3 was that the fans didnt switch off so drained the battery, I guess this time round its slightly better as its just noisy but at least switches off when the car is off!

I guess at some point I am going to have to replace this larger fan and just wondered if anyone had the part number for this as Audi want to sell it as a fan kit which is £242 OUCH!

Would part number 1K0959455DT fit and can I use the existing cowling or has audi changed the hole positions to mount the fans?

I have an 04 A3 2.0 FSI sport engine code AXW

Some more info incase I didnt make it clear above, it is the large fan that is making a noise! This looks as though it comes on with the smaller fan when the car is hot (smaller fan sounds ok).

When the car is cold and I turn the climate control / air con on the large fan kicks in and gets noisy, the small fan does not run at the same time when cold and when this is turned on! When I turn the climate off takes around 20 seconds and the large fan stops....?

From what I have read it seems as if the larger fan has 2 speeds, low speed and high speed and from hearing it I imagine that it only runs at high speed hence the loud noise, which means that something is stopping it running at low speed, does anyone know the cause of this? Some people mention burnt out resistors etc within the fan which stops it running low speed!

Is the only way around this to replace the larger fan or would an auto electrician be able to split the fan open and replace any burnt out resistors / fuses?