Airpot Express - Upgrade amp or DAC?


I have a pair of KEF Q300s running through an Audiosource - Amp 100, fed by an ethernet wired Apple Airport Express. I'm running uncompressed AIFF files via iTunes.

What's my next updgrade, a DAC or amp? In comparing the Airport DAC to my Yamaha RX-V1900 DAC, the Airport sounds awful. I'm definitely leaning towards a DAC, but I wonder if people have other suggestions.

Regards,

Andrew
rooty-j
Steve N (Empirical) - In your 1/13/13 post, you said that you'd done comparisons of various sources, including the AppleTV. How would you rate AppleTV vs the other computer sources and in general vs run-of-the-mill DVD players? Thanks.
Steve, would it a better solution to stream music to a 2nd/3rd room to a laptop hooked up to a USB dac. Hence cutting the Airport/AppleTV out of the equation.