I just purchased a 4 wire speakon to speakon cable to attach my Behringer EP 2500 power amp to my Avatar B210 and B115 cab combo and it doesn't work right. When I use a speakon to 1/4 cable all is well. Do I need a 2 wire speakon to speakon cable? I thought 4 wire was ok, but maybe Avatar uses something in their setup that makes this not work since they have 2 1/4 jack and a speakon. Any help for a newbie here would be greatly appreciated.