yo bbr! I have that problem if i don't have my walkman plugged into the computer when i start up win amp, try closing winamp and then starting it up while the player is plugged in and that might allow you to use it. when you do that, it appears under "Portables" rather than "Devices" - or the other way round, I don't recall.
I have a bug where my database just stops at "S", when I browse across the initials of my artists. Anything beginging with T, U, V, W, X, Y, Z, just ends up being lumped under "S". Are there any easy ways of repairing my database?