Seadweller,

have looked at your speaker connections? Sounds maybe there "might " be a phase issue.

I had a similar problem with another set of speakers....

sorry if you have all ready went through the trouble.

I have 604-8k's and at very low volume the bass is a little anemic, but when I crank it up , I get bass. Plus it looks like I will have to do some acoustic panels to help tune the room. I have a bass nodes when I walk around. DO you notice an increase/decrease in the BW when you walk around while listening?

-chris