Game Sound Volume/Level

[Horace Ho]

When I try to retrieve the GameSoundVolume via
PrefGetPreference(), it always return 0 on a 
PalmPilot (Personal or Pro) ROM. I tried both:

 PrefGetPreference(prefGameSoundLevelV20);
 PrefGetPreference(prefGameSoundVolume);

On a Palm III, the second call returns a good
value, 64, 32...; the first call always returns
0.

Any hint?

Thanks
horace