Usually people jump to help out in these forums, I'm assuming from everyones silence that it might not be possible to decrease the volume on the voicemail alert???
On the BOLD you open the active profile for editing and you will see a list of all the various types of alerts for phone, email accounts, sms, mms, etc. when you select one of those alerts to edit you get a screen that allows you to select vatious options (vibrate, or ringtone, number of vibrations, led flaching, etc.) The item just below the selection of the ringtone is the volum level. You can go from mute, low, medium, loudn or increasing.
On the BOLD you open the active profile for editing and you will see a list of all the various types of alerts for phone, email accounts, sms, mms, etc. when you select one of those alerts to edit you get a screen that allows you to select vatious options (vibrate, or ringtone, number of vibrations, led flaching, etc.) The item just below the selection of the ringtone is the volum level. You can go from mute, low, medium, loudn or increasing.