You really shouldn't be pushing your output that hard . . as soon as you go beyond 100% you're likely to induce digital distortion, which sounds just awful really. If anyone has to put the volume output up to anywhere near 400% there's either something really wrong with the gain structure of your audio setup or the video file itself was encoded incorrectly (non-unity gain) . . I'm assuming it's the latter in this case.
At the end of the day it's going to be easier to fix the video files than to keep trying to adjust for them . . you can adjust the audio file in the container without affecting the video stream which is great, a single batch process on all the offending files would fix the problem.
IF it's ALL video files then I'd basically do what SledgeDG
suggested . . I'd set your media program's volume output at 100%, set windows' volume output at about 90% (most op-amps in consumer audio devices can't handle transients beyond about -5dB) and just turn up the volume on your amp/speakers . .
What amp/speakers are you using by the way?