@Vincenzo -- That may have been true a couple of years ago, but wireless technology has improved to the point where a wireless connection will probably serve you just fine. If it does not, you might want to make sure your router can handle the most current (and fastest) wireless speeds or that your router is in a location that provides a strong signal all over your house.
Whenever I have had problems with wireless routers, range has usually been the issue. It is a good idea to keep those routers up high and in the center of your home. Make sure you are getting a strong connection between your equipment and the router and you should be able to stream just fine.
Another problem I have had has had to do with the wireless channel on which my router is broadcasting. There are "sniffers" you can download that will tell you which channels are being used by other routers in the area. Find a little used channel and switch to it (if you need some help with that, consult your owner's manual).