Using DiskWriter in Winamp 2.x / 5.x
(I get asked this a lot)
It's available in Preferences:
Under Plug-ins, Output, make sure the Nullsoft Disk Writer plug-in is selected:
To change it back, select whatever you had before: waveOut, DirectSound etc.
Also, since
PSF2 files play at 48KHz, you can go into the
Highly Experimental configuration and force it to resample to 44.1KHz: