A number of users have reported a sudden drop in volume on their Galaxy Nexus devices while on an ongoing call or otherwise. Users have complained of frequent software bugs, which randomly drops the phone’s volume down to zero. This very simply means that all the notification alerts and alarms are silenced, rendering some of its features rather useless.
Quotes from some users:
“Got my Galaxy Nexus yesterday, and while it’s mostly great, there’s a pretty massive flaw which makes it almost unusable as a phone: the volume seems to randomly drop down, which means all notifications are silenced.
“It’s happened to me more times than I can count, and other users are experiencing the same issue”