Should I use long interconnects, or long speaker cables?

Currently, my equipment rack is placed centered between and behind the speakers.  I’m getting acoustic feedback (rumble) from my tt due to it’s location.  Successfully, I have eliminated this rumble by using a KAB rumble filter.  However, this seems to me like a bandaid approach, and I would like to try to eliminate the use of this filter if possible.  I’m thinking of moving my equipment rack to the side wall to try to eliminate the rumble filter.  My question is, there are two ways to do this.  Is it best to:
#1). Move everything (including the amplifier) to the side wall, and use long speaker cables to connect the amplifier to the speakers.  
#2. Move everything, except leave the amplifier on the floor (on a separate amp stand), and run a long interconnect (20’-25’) from the preamp to the power amp (my preamplifier is single ended only)?
In advance, thanks for your guidance!
How long is long? 5 to 7m length speaker cables is still manageable. Some amp manufacturers such as Naim actually recommend to have longer speaker cables for optimum results (better sound).
My one question is how were you able to daisy chain cable and anti-cable without them annihilating each other?

This is funny!  Sorry to quote you twice in one day...I'm not stalking.  

+1 that balanced interconnects are the solution here.  

Given the obvious advantages of balanced/XLR, I wonder why more gear just doesn't have it. Even if it's not fully differential through the unit, the signal transport is far superior. I know, it probably depends a lot on the preamp design...

One other point - Tascam and Henry Engineering make some pretty good quality single-ended to balanced converter boxes. You might not want to use them permanently but it's a decent interim/testing solution to see what kind of degradation you're getting from single-ended runs and whether a balanced connection would be optimal.  

For long speaker runs use NVX 8 gauge OFC copper silver plated..
Always use Balanced XLR's if possible..
I think the standard recommendation for ”long interconnects/short speaker cables” first came about back when everyone was using tube amps and zip cords. I’m not so sure it’s as important with the ss amps and the heavier gauge speaker cables often used today.