Sorry, but the barking comes with the breed.
"These little dogs like to bark (their barks are surprisingly loud for their size) and are compulsive diggers."
-From
http://www.dogbreedinfo.com/dachshund.htm, the first result to a Google search for "Dachschund"
Honestly, you should consult a professional trainer or behaviorist in your area. Has anyone video taped your dog while you are away? Is he barking out of separation anxiety? Has the barking been reinforced by someone letting him out of his crate when he barks? (i.e., bark = get let out)
As a quick fix, you might want to give him something to keep him busy while he is in the crate. If he is chewing, then he probably won't be barking. Have you given him a Kong?
http://www.kongcompany.com/ What about a bully stick? A
raw bone? (A crate is a great place to give raw bones, and most dogs love them)
By the way, how long are you leaving him at home? He's only 3 and 1/2 months old, so anything more than a few hours is going to be rough for him.