Cracking sounds inside hub

[mstanescu]

Hello all

I have the following problem. if i apply more force in pedals (like standing up from saddle and accelerating) i hear short cracking songs ( like a person walking on a loose wooden parquet or while sitting down on an old chair)

I removed rear wheel from frame and i can reproduce the sounds by applying force to rotate the sprockets in the normal rotation direction while keeping the wheel steady with the other hand. Seems like its coming from inside the freehub mechanism. The freehub seems to rotate very well without deviations.

I have M-wing hub and Shimano XT cassette.

Any ideas what is the cause?. Could it be water or dust?

Thanks
Mihai