Had my 04 TL sit in the garage for half a year. Just got it insured yesterday and everything works very good. (Oh god, I almost cried when I finally sat in my beloved car)

Then I noticed that when you adjust volume in "setup", when you adjusted it will give you a beep sound to test where the volume is at. I did that and the feedback was not a "beep" it was more like a lot of hands clapping.
At first, I thought it would be just another preset sound beside the beep I had before, thought the clapping was pretty clear and funny but didn't bother.

Then I noticed that when I use the navigation for route guidance, every time it tries to speak it gives me the hands clapping sound.

The sound sort of sound like a blown up speaker but you can still clearly tell that the sound are hands clapping.

HFL and music audio all works fine. What would be the problem?

I'm guessing it's only the navigation speaker since the HFL and audio system comes from all the other speakers.
But where is the navigation speaker located? and what's the specification or which speaker I would need to get to replace it?

I'm a mechanical dumbass, but I don't want to take the car back to dealer for that huge amount of labor fee.
Help please?