They can make some noise when engaging or slipping but if it's all the time you may have a problem. Firstly check the fluid. They take a special fluid as well.
I personally don't think Polaris or Canam has much to worry about when it comes to other manufacturers coming out with new units. Even though both Yamaha and Honda builds a reliable machine, the razors and Mavericks have proven themselves in the marketplace and have several years development ahead on the sxs market. Now that's again my personal opinion.
I just posted the same thing. Its a shim in the front diff. You can take it out and it will probably be quiet but its a job that requires a press and a new seal. Im going to get a stereo and forget about it the best I can. It's soo annoying, wtf was Polaris thinking