[LAU] hdsp, mpd and lyrcing

Hi! For "lirc-ized" playing back I use mpd CLI client. As far as hdsp driver hasn't common "Master Volume" (or such) alsa control, I use mpd's "software" volume leveling, so lirc commands are directed to CLI mpd client. To have some reserve in volume I set amplifier's volume regulator higher than, say, is needed at current moment. As a result I have software level noticeably below 100%. I suppose such software volume regulating eats samples resolution (and, at least theoretically, sometimes I have, say, 12-13 bits rather 16). Am I right? If "yes" - are there ways to use lirc to set a volume level more directly communicating with hdsp driver via CLI? Will such way keep sample accuracy?