Went to Radio shack to buy an AC/DC adapter for my Rio, as I wanted to leave the nice little one it came with in the Pelican case full time - bought this big hulking brick of power supply, rated at output of 1000mA, 12VDC - works, but not really. Constantly get the little 'battery +-' symbol (low power) on the player, and it occasionally powers off, then back on again..

I know, I know - I should have read the AC/DC Power adapter FAQ first, but really - who woulda thunk it!?