My Messagebox is silent i don't have sound
I think it 's a bug related problem Qt Version 5.xxx

I have a serious problem with the new version Qt
When I use the standard dialogs, appears without a sounds in the dialogue were.

this bug existing on the new versions of qt for windows only (5.xxx).
i not testing on others OS.
When i using of qt version 4.8.5 with mingw 4.40 don't have any problem. but when i using the last and new versions of qt on windows XP or 7 This problem occurs.