Where is the "DING"??

[jobaker4]

Hello all - I am wondering if this is a problem or normal, my other X never got these warnings so I am not sure if they are supposed to chime.

I have had the Low Tire Pressure Light come on a few times but it does not "CHIME or DING" when it comes on to let me know it is there, is this normal?
Also this morning I had the "CHECK BRAKE LININGS" message come on at some point in my drive but the CHIME never sounded, shouldn't it ring once to alert me?

Please let me know if you have had any experience with this, it seems that there should be some sort of acustical signal to get your attention for these messages.
Thanks!
-Josh

(my car is a 2005 X5 4.8is by the way, 21,000 miles on it)