Thanks @stereo5 I think that is the route I will go down. For my own understanding, is this a turntable feedback loop? The low frequencies being put out by the speaker are traveling along the floor, into the rack, picked up and amplified by the cartridge and phono pre and sent back out the speakers further exacerbating the issue?
I really appreciate everyone's responses. This has been a big help....
I really appreciate everyone's responses. This has been a big help....

