If you can, i would pull the 160 away from the wall a little bit...
Also, in the mean time, you could use some blankets as sound panels... if you dont mind putting a couple holes in your wall.... hang the blankets from the wall to get rid of the hard surface of the wall.... That is what i personally would do in the mean time. i would think 1 blanket on each wall would be sufficient to tell you if you are having an echo problem...
i would also verify each end of the cable, both on the speaker and the receiver, or what ever you are using for power.
