wasapi is a windows plugin or driver so not needed.
I personally use mpd+gmpc. That's music player daemon as my music server and gmpc as the gui for that. It works great as long as you have one main folder where all your music is in it and it does require some work to use it as you have to set up the folders and permissions. Also the UI is great and pretty easy. There's a database that shows you your folders like a tree view and then you can click on your folders, subfolders, etc.
I don't know what kind of linux you have but if you have ubuntu this could be a good website to set it up. That link uses sonata as the gui but I have gmpc which is a better gui but there are many different ones. You can choose which gui you want unless you want to use the terminal.
Second MPD...plenty of front ends for it, just Google MPD wiki and look under clients.
I am using it with a headless MiniITX computer and controlling it via Minion in Firefox or an iTouch.
If you don't want to fool around with configuring etc. and just want a good player try DeaDBeef. IMO, its the Linux version of Foobar, it even has an outstanding built in EQ with which you can import Foobar's presets or make your own.