Factory Nav - Hands free issue with Phone

[mkdiehl]

Is there a way to upgrade the hands free phone hardware in our car? I get complaints that the quality of the system is bad when using this feature. They say the background noise is quieter than when using the handset but the voice quality is "tinny" etc.

My job requires a lot of driving and phone calls and would like to be able to use this feature more without making my customers deal with the bad quality.

Thanks in advance
matt