I set the sound on the PC to 30% and use the HU. The reason being is that my HU can do much more quaility functions that any PC.
How are you tuning your speakers, amps? Are you setting a permanent volume on either the amp or hu and controlling volume from one or the other. Also are you using the equalizer in the hu or a software equalizer on the pc? Any type of info in regards to how folks are tuning there sounds is wanted. I'm just trying to get some ideas as I find myself tweaking things a little too frequently.