Hello Leutz, I have installed my *not laughing* active sub today. Now the part whistles and chirps powerful loudly when the engine is running. I just rummaged a little bit in the forum and experienced that you should move the chinch cable separately from the power supply. So far clear, I will still do. But now I still have the test, which the sub goes too quiet (is a Ravenland AXT 1000 II). I have two chinch pairs (rear and front) on my radio and have the sub now to the front connection. can this be related to it? However, my fader is on +/-0. It’s quite time-consuming to try the other connection.