I have found that in general, the bigger the room, the less sound treatment it likely needs it. No idea what speakers etc you're running but as said previously, make sure the speakers them sit firmly on the bare floor or w/ spikes going through the carpeting. Then maybe try spacing the speakers further apart & then toeing in them even up to a 45 degree angle. Also, try slightly angling up the speakers and inch or so in the front so the midrange & tweeters are more directly facing your your head.
Also, completely differently, try disconnecting all cabling & cleaning the cable ends & whatever socket or connecter they go into & replacing them.