I have not read all of these theads, so this may have been handled. Do not stuff anything in your ports. The ports are designed to give you a flat or smooth bass response down to a speakers given ability.(Some small speakers build a bass boost on purpose). If you are using quality speakers, you are dealing with a room problem amplifying a given bass frequency. Try moving your speakers out from all walls, you have an underdamped amp, change your amp or even cables for control. Or you can change the speaker design slightly. The way to remove boom is to remove the port and exchange the port tube. You will need to lengthen it. This lowers the tuning freqency and will also decrease any bass hump caused buy tuning. If you shorten it, you will create more bass at probably an undesireble frequency.
I hope this helps.
I hope this helps.