hp desk top

i have a hp desk top windows 7 with coax out running into msb link ,running into amp ,im using the volume on desktop,apple itunes with eveything running apple lossless, does anyone have suggestons to make this set up the best without buying anything else..im running a tara lab air coax cable to dac
ITunes does not play well AT ALL with Windows. Since your library is in ALAC format, Get the free Foobar software media manager with ALAC decoder module, and activate one of the better software audio drivers (included) such as WASAPI Event. If at all possible, set your computer output to max volume and use the best hardware volume controls that you have downstream.
Or, convert your ALAC files to AIFF and buy JRiver which is a more user friendly setup than Foobar, but doesn't support ALAC very well.