All the comments about speaker placement are well considered. But it’s worth noting that loudness controls or buttons are rarely well calibrated to do what they are intended to do. The best of them are either rotary controls as on many Yamaha models or are linked to an AV receiver’s setup mic processor as in Dolby Volume. If you have a preamp with a loudness button and a power amp with input level controls, you can reduce the exaggerated effect of the loudness by lowering the amp’s input level. But lacking any of these you have no better option than to turn it off!
How to damper booming bass...
Other than turning loudness off, is there any way to lessen booming bass? Maybe stuffing up the ports in the back of the speakers? What do you think?