One more thought: Make sure that the black wire from the REL is connected to one of the negative (probably black) speaker terminals on the amp, and not to one of the positive (probably red) speaker terminals. If the black wire is interchanged with either the red or the yellow wire from the REL, and is connected to a positive speaker terminal on the amp, I believe that could account for all of the symptoms you have described here and in the other thread that was referenced above, and (consistent with what you have reported) could result in the amp shutting down even if the sub is turned off.
Regards,
-- Al
Regards,
-- Al

