You may try shifting the speakers around the room until the sound stops overlapping, failing that, You could try acoustic tiling to change resonance. If that's too expensive, pillows nailed to the wall over boards work just as well, no joke.

I can't make more educated suggestions unless I have an idea of the speaker placement in the room and the size of the room.

My Dolby 5.1 is set up with the satellite speakers all equidistant from the TV to give best sound to the individual sitting directly in front of the TV. Depending on where in the room you are, the sound overlaps a bit, and sometimes it can be difficult to distinguish where the sound is supposed to be coming from. Hieght in the room relative to the floor also has an effect, the closer to the cieling they are, the less bass transmission you get, and more trebel bounced from the cieling. Lastly, even the carpet you choose in your mancave can have an effect on the sound transmission. My Woofer sits on a low density pile shag rug, and it has to be turned up much louder to get the same effect as when it was on the hardwood, but there was a lot of rattle with the hardwood floor. Remember, flat, non-porous surfaces deflect sound, while porous surfaces tend to absorb sound.

It's a PITA to set up a mancave, it took me nearly a year to optimize mine.