Avanti bike creaking noise...?

[HeLeX]

Its a 2012 Avanti Aggressor 29.1
Ridden 2500km, bearly done off-roading, 98% done on the road.

Every time I sit on my seat I hear a clunk noise, then If I release the pressure off and sit back on it I hear it again. It is definitely coming from below the seat post. I have switched seat and seat post and that doesn't solve the problem.
When I release of the seat and pedal, its fine too. When Im off and press down with force on the saddle it also makes the noise...

My friend has heard the noise too, he said it is coming from the bottom bracket/ crank area...

Any ideas? There are NO frame cracks, it happened all of a sudden when I was riding yesterday...


P.S. No noise happens when I pedal

[nfmisso]

Some pictures would be useful - I have never heard of Avanti bicycles. Does it look something like this:
[attachment=3952]

[okers12]

I have the same exact problem. Any luck?