Deactivating the sound pack doesn’t go into effect until a restart of the client.
Title and post are not the same content (that confuses me).
My guess is you report a TS3 client issue.
There is no way to deactivate a sound pack in TS5. Only turning down the volume or deactivate single notifications is included.
In TS3 Sound packs are active in settings and per connected server tab.
Changing settings in general doesn’t mean that the current used sound pack does change.
Please give us some more details or how to.