Hi from Finland.
I used to have an unexpected noises that people guessed it might be because of broken speakers. But as far as I was experienced in same kind of noise from Sonata 95 when I was in Korea. I knew that coudn't be because of that. I thought something might be too loose so that it vibrates. I opened the door panel and looked into it. The problem was the vinyl plane that is meant for water proof for the speakers. Vinyl one is stuck at top of the speaker area but bottom. So that it vibrated by speaker's bass. I tightened it up just by tape(I hope it last long). So if anyone having same problem as I did you better tighten up the vinyl materials(only need to remove door panel and speaker - then you will see the vinyl). Now I got a really brill bass (which is better than it can be expected) by original audio + speakers combination.
I used to have an unexpected noises that people guessed it might be because of broken speakers. But as far as I was experienced in same kind of noise from Sonata 95 when I was in Korea. I knew that coudn't be because of that. I thought something might be too loose so that it vibrates. I opened the door panel and looked into it. The problem was the vinyl plane that is meant for water proof for the speakers. Vinyl one is stuck at top of the speaker area but bottom. So that it vibrated by speaker's bass. I tightened it up just by tape(I hope it last long). So if anyone having same problem as I did you better tighten up the vinyl materials(only need to remove door panel and speaker - then you will see the vinyl). Now I got a really brill bass (which is better than it can be expected) by original audio + speakers combination.