No where in your set up instructions do you tell us that you need to convert all songs to MP3 format. You say use windows media player, this does not have a MP3 converter. When eventually sussed out it is good.

I have used this MP3 player for 2 weeks, it is really a nice one. It can play music which is 320kb/s. Besides, the size is great, it is not too small to control or too big to carry. However, the only problem is NWZ-B183 has no radio, I would prefer to buy NWZ-B183F if I knew this on the website. The push-buttons are all dark bule, not like the photos showed on website.

I used already many mp3 players, but I think that's the best.