Best xlr interconnect for Meridian

I am having problems with a Meridian 596 DVD-CD player. The unit is lifeless (like the bottom fell out) when hooked directly to the pre-amp and used as a player. I have a Audio Research LS-15 pre. When I hook the 596 to a Meridian DAC, the unit sounds much better, although a tad bit bright for my liking. Meridian is noted for its laid back sound so I figure that something is lacking. The DAC goes through the balanced inputs of the LS-15. I am using Monster "M" series cables from the amp to the AR, Analysis Oval Nines. I have some cheap interconnects supporting the balanced inputs. I had my equipment stacked together and I noticed that when I separated the DAC and the 596 from the amp and preamp everything seemed to sound better. Prior to purchasing the Meridian, I had a Cal Audio Delta that did not pose any problem. Any one have any suggestions??? I am desparate and my wife is getting irritated every time I mention anything relating to audio equipment. Thanks...
My suggestions are:
1) Separate the components and have each stand on their own shelf, especially the pre-amp. The feet on your pre-amp are setup to isolate vibration. It is generally a good idea to keep components 3-6 inches from each other.

2) Get rid of the monster cable and your other so called "cheap interconnects". I am not saying to dump megabucks on cables unless you are so inclined - just get something good. Some suggestions are: Zu Cable Warmouth, Wasatch Cable Works 105 or 205 or Audioquest Python
3rd thing -- make sure the tubes are good in your LS-15.
4th thing -- if you like to tweek, some good NOS tubes by Telefunken or Amperex will work really nice.
J_k knows his stuff. Also, Cardas interconnects are another suggestion.
I am currently using MIT shotgun proline xlr cables with my meridian 566.24 and has great results........very detailed and smooth sound. Hope this helps!
Harmonic Technologies Prosilway 2 XLR ICs. I have a 508.24 going into a Krell KCT and this really opened things up.