Your speakers are finicky as respects placement. Most who have them in a smaller room have them placed along the long wall. You may try moving things around a bit before spending more money (and time) on new speakers. How far do you sit from your speakers...and how far from the back wall (or corner, I guess, as you have them on the diagonal) do you sit? What type of music are you listening too? Do you have some very well recorded, non-compressed CD's to use as a reference? What are the power cords on the amp & CD player? Have you done a polarity check to make sure all is proper?