Guhde, today I connected the subwoofer via chinch cable to the sub-out on the radio (was previously running with y-plugs over the end stage). now I have the problem that the subwoofer does not operate at all seperat, although on the radio everything was set correctly. is it possible that the end stage is internally brimmed? at the moment it looks like this: subwoofer brimmed on channel 3 and 4 the 2 normal boxes quite normal on channel 1 and 2 when I now connect the chinch cables from the normal boxes, run t all at once everything (so sub and boxes) and from channel 3 and 4 does not come at all, no matter what you connect there. endstage: hiponics son of europa