Really quick, sorry if this has been answered somewhere where I can easily find it I just figured I'd make a topic.
I opened up FH today to mess around in map maker for fun and I always had my music and stuff turned off in the settings so I turned it back on but effects sounds won't play like at all. Like if I hit a button (for example the login button) no sound will play. And yea I have my sound settings to default now but no sounds play, all I hear is the music. And if I turn off just the music and leave effects and GUI at 1 I still don't hear any effects its just empty quiet and I have no clue how to fix it or what happened since I haven't done a single thing with FH in forever.
Have you tried re-installing FH? That's one way to fix this (and many other) problem(s), just be sure to make backups of anything you want to keep (maps, markings, items, presets, my_presets, textures, etc...).
It sounds like something might be missing from your current FH installation.
You can also simply use TwistedSorrowz's method for convenience. =)