I know when using foobar, you can set the preamp level to -8db in preferences to prevent clipping. My question is, can you do the same thing in Winamp? For instance, setting the volume at 65% instead of 100%

its a while ago since i used winamp. does the slider change the windows-mixer volume / global directsound volume? Or does it only change the volume in relation to winamp?

It's only winamp-based, so it should work.