I just bought two speaker cables with Neutrik NL4FX connectors. They work fine for my Genz-Benz GBE, but I get no sound when I use them with my Markbass LMII. My existing cables, which have the NL2FC connectors, work for both amps. I've contacted Markbass but have not heard from them. Is there any reason the NL4FX should not work with the Markbass amp? I'm hooking the heads up to Accugroove cabs, in case that makes any difference. THANKS!