Typically all the volumes on a Xerox device are in around the admin area ala Machine Status > Tools > Device Settings > General.
But I don't have a 3335/3345 model to confirm that it is exactly there, and don't know what tech the device is based on, so I can't confirm. I messaged a guy who has one, he didn't respond.
We bought 2 WorkCentre 3335s. One works nornally. The other makes a loud BEEEEEEEEEEEP every single time it prints. It is driving everyone in the office crazy. I've gone searching thru admin and user manuals, nothing at all in there about sounds or beeps or silencing. Has anyone experienced and can suggest anything before we just have to return it?