Sealing ported enclosure to reduce boom

Agree with Pani. Try using the Sumiko Master Set method to set up your speakers. It will take a while but you will learn to find the bass nodes in the room and correct for any boominess.

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.

Find out how the port is being employed by the speaker - in other words, find out what frequency range goes to the port. If that is the area you need to cut, then you should consider it (might want to discuss with the manufacturer to be safe).

My dealer had to stuff the ports to get Wilson Sashas to work in my room. In my case, it reduces the lowest frequencies, but that's what the room called for.