I have test mortar today and i agree, no sound of incoming mortar...
And you can do it simple than switching :
Crate a player with a mortar bot under his command, order the bot to aim at you and he will firing at you

i dont think mortars make any noise in real life, theyre just explosives being launched, kind of like the 203. that incoming sound may be just hollywood effects. just my $.02, ive never been fired at by a mortar so i dont know for sure

Mortar definitly do a sound, look this real life video :
http://www.youtube.com/watch?v=6dXJmZnEWqg
You can clearly hear the sound of the falling mortar

Marlon you are actually wrong. Here is a example of a incoming mortar. Its better sound in this video than in Arma 2...

http://www.youtube.com/watch?v=ImNvrVSNiGk

Marlon, it's definitely not the high pitched whistling sound you hear in movies, but you can definitely hear it. I know for a fact that mortars arcing over head sound like a jet that's fairly high above.

This issue was processed by our team and will be looked into. We thank you for your feedback.

Please keep the issue monitored to see when it is fixed.

@Marlon
any ammunition, dumb, guided or propelled, makes a sound when heared from the front because of the stabilization fins (example of other "hearable" ordances are Mk82, GBU12 and other bombs)

I was an arty spotter in the finnish defense forces and the sound made by falling mortar shells was barely audible. But then again, I was always 1km away from the target.

Almost a year later and still no change.

Can we please get a fix on this?