palmOne Treo 650 Using Manual page 187

Setting system volume levels
You can set the volume level for system sounds, such as the tone that plays when you
synchronize.
1. Go to Applications
2. Select the Application pick list and select General.
3. Select the System Volume and Game Volume pick lists and select a volume level.
4. Select Done.
and select Sounds .
If the Ringer switch is set
to no sound, the ringer
setting overrides the sound
settings and all sounds are
turned off.
Your smartphone includes a
silent alarm that can vibrate
even when the Ringer
switch is set to Sound Off.
System sound settings :: 185