If the rooster is a Silver Laced Wyandotte, I would expect all chicks to show silver.
If you are getting some brown chicks, then either they have a different father, or that rooster is not pure for the silver gene.
A silver rooster does not produce sexlink chicks. For gold/silver sexlinks, the...
A rooster with white barring does not produce sex-linked chicks. He can give barred sons and also barred daughters.
To get chicks where barring indicates the sex, you need a barred mother and a not-barred father. Then the sons will show barring like their mother, and the daughters will be...