Slow to show on PS3

Wireless could be the problem. I use a wired connection and I also had the same problem at first. The biggest thing that made a difference for me was that I had a switch/hub connected to my router. I unplugged the cables from the PS3 and NAS and instead of them being fed through the switch I connected both of them directly to the router and it fixed the problem. Another thing I have noticed is that if you disable the Disk Spin-down Option it will help a little (in my case a second) it is not much difference for me but it may be a huge factor when using wireless. If you can get a direct wired connection that would be your best bet.