On [XXX], at about 3,500 miles, the subwoofer speakers in my 2025 Honda Civic Hybrid Sport Touring began rattling persistently at moderate volume (14-15), disrupting the entire audio system. The component malfunctioned, no failure in the traditional sense, but it renders the sound distorted and unusable, far from the advertised premium sound quality on Hondas website. Its still in the vehicle, available for inspection if requested. This dsnt directly risk physical safety, no crash or injury, but it severely impairs the driving experience, as the audio system is a key feature I rely on, now reduced to a constant, irritating rattle. The problem has been reproduced and confirmed on all the other vehicles of the same model and trim at the dealership where I bought it, Honda mall of Georgia in Buford, GA. I took it in for repairs twice, first on March 25, then again on April 2, and it spent 7 days in the shop total. Both times, the rattling persisted unchanged. The service team acknowledged its a model-wide defect affecting other Civics of this trim, yet no effective fix was applied. The manufacturers regional representative inspected it indirectly through the dealership and declared the rattling normal, refusing further action. The service manager promised an engineer would investigate, but that never happened. There were no warning lamps or messages prior, just the sudden onset of the subwoofer speakers on the rear deck rattling on [XXX] with no earlier symptoms. Its been consistent since, worsening the audio with every use. The dealerships confirmation of a widespread issue, paired with the manufacturers dismissal, points to a design and quality control flaw they wont address. This isnt a one-off; its a systemic problem ruining a core feature thats been happening for a decade now with the top tier trims of Honda civics. I request an investigation into Honda on why it hasnt rectified this issue when Honda promotes premium sound. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT