Do the right lights and numbers or whatever come on? Mine (different brand)has a digital display that shows the minutes of the full washing cycle when I hit the button, then I have to hit it a second time to actually START it, and thats when I hear that ker-thunk you spoke of that clicks the locking thing in place then another few seconds later I hear water noises, etc.
Mine will make an OBNOXIOUS alarm sort of noise if the door doesn't lock..an angry noise! LOL Once my door closing piece..little teeny plastic piece (the "male" piece from the door), had broken off and was stuck in the "female" piece on the machine, so it would not actually latch. I now know that this full piece gets lose often, so I have to just push it on (its about 3 inches long..and the little "male" thing I am talking about is a part of it).
Also, one time my rubber seal somehow got tweaked..again, making it not seal.
Not sure any of that helps you..just some of my experiences where I wanted to SCREAM about this new machine of mine, and it turned out to be really little dumb things easily taken care of. After the little "male" thing broke off..it was a big deal to reorder the piece...so hubby ordered 3! They were only like $5 each but a PITA to get here (had to order online...not avail to go pick up locally).
Also, try googling the exact model of yours...I had an issue with mine and leaking..and I was so proud of myself that I googled it and discovered the problem. DH fixed it via the instructions I found online (PITA issue..but it was the right stuff!). Other people out there may have had this issue and already simply resolved it
Good luck!