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!