Toyota Refused to Replace My Rear Speakers Under Warranty

I took my Toyota vehicle, which is under warranty, to the authorized service center for maintenance. I also informed them that there was an issue with the speakers, specifically that when I listened to upbeat music, a creaking noise came from the rear speakers. After the maintenance, they told me there was no issue with the speakers themselves, only with the settings, which they had adjusted, and advised me to return if the problem persisted. After leaving the service center, I tested the speakers for about 10 days and noticed that the creaking noise was still present. I took the vehicle back to the service center and checked it with the technician. He confirmed that the front speakers were fine, but the rear speakers still made a creaking noise when playing upbeat music, and said there was nothing they could do, sending me away without performing any repairs. My request is for the blown rear speakers in my vehicle, which is under warranty, to be replaced.