Using long interconnects with your turntable?

I'm having some serious rumble issues with my turntable when I turn the volume up (Music Hall MMF-7 / Goldring Eroica high output moving coil cartridge). The rumble starts between 85 - 90 db.

I've tried everything from Mapleshade 4" block, to TTweights Isofeet, to a Ginko Cloud but nothing seems to help. The table sits on a Mapleshade Samson rack between my speakers. The speakers are roughly 4 feet to each side of the turntable.

I really don't think that the rumble is due to structural problems, I think it's acoustic in nature, because when I put my head directly over the table, I hear a bad bass node.

My two choices are to:

1) use a rumble filter (KAB?)
I'm not too keen on the idea of using a rumble filter, but I hear some positive remarks about this thing. Any thoughts on this?

2) move the turntable
In order for me to move the turntable, I need a 25 foot set of interconnects. I don't want to spend a ton of money, but I don't it to sound either bright, or rolled off in the top either (and I really don't want any noise or hum problems due to the length of the interconnects). I've read a lot of positive comments about the Kimber Hero. Any thoughts, suggestions and/or recommendations??

In advance, thanks for your input.