Port noise is well known, especially with smaller speakers where bass signals too low for the port to be effective are present.
It could be that the screws holding your drivers are loose, worth a check and see. But otherwise the speaker is simply being played too loud or you'll need a crossover to filter the bass out (and probably a subwoofer to do the bass).
It could be that the screws holding your drivers are loose, worth a check and see. But otherwise the speaker is simply being played too loud or you'll need a crossover to filter the bass out (and probably a subwoofer to do the bass).