How long does it take for carbon brushes to wear in?

[milkywaystar]

My brand new Indesit washing machine is a week old, i have used it about 4 times but i can still hear crackling/sparking inside when it spins and if i look right underneath the machine i can see the glow of sparks. There are no sparks flying out of the bottom of the machine or anything. I can hear it more when it spins clockwise than anticlockwise. I cant hear it at all when it is on the fast spin cycle, just when it is at the beginning of the wash cycle and it spins slowly. I am presuming that this is just the carbon brushes bedding in but how long should it take to bed in? I've heard different opinions from 1 wash to 10 or 15 washes?

 

[rocks1]

It's about 10 washes , you can put it on fast spin only for about 8 times to bed them in.