You may have already done this, but your speaker/listening position should be dialed in. Then start with room treatments. The best tools for this are an inexpensive laser level with a straight line and an RTA. The Behringer DSP8024 and DEQ2496 RTA/EQ's are very powerful tools. I do not connect mine "inline" as a cure. Depending on how experienced you are there may be a big learning curve. You'll know where your room problems are and be able to see as well as hear the results of your acoustic treatments. Most of us are dealt a less than perfect room, with these tools you can maximize what you have to work with. Also, you may not be able to detect the impact of many tweaks until your room/setup is maximized.