"Mark Activated" vs. "Mark Deactivated"

[Marshall handheld Flax <m.droid.flax@xxxxxxxxxxx>]

Everytime I do a C-SPC in a normal window and toggle between having a mark and not, I hear a "thump" sound. 

It makes perfect sense to have a sound rather than a verbal announcement in this case -- but to my ears the sound when mark is activated and the sound when mark is deactivated sound identical.  I'm assuming that the proper mode of behavior is to have two different sounds for the two different modes ... is there something I have misconfigured?

Thanks so much!

Marshall

p.s. As always, I'm a sighted guy who is just imagining what it would be like for a blind user.