Tunze Turbelle 6015 noise

[Quercus]

Due to the large chunk of wood in the centre of my tank (which I am now rethinking), there are areas of poor-to-no flow at the front so I have bought a Tunze Turbelle 6015 pump to try to improve things. Have just turned it on and it is obtrusively noisy! After reading all the reviews that said how quiet it is, I was surprised as this isn't quiet at all. Is this pump likely to be faulty or do pumps need running in before they quieten down?

 

[Tropicaltanklover]

I don't know about this particular pump, but my past experience of them is that the different ones I purchased were all noisy.
I have just set up an under gravel filter tank in my office at work and tried 2 old air pumps. The Interpret one could wake the dead, and a Chinese unknown brand was significantly quieter but I will have to live with humming.