A couple thoughts: In profiles, can you set a notification for when a call connects? (I don't have BB OS 7.) Or, have you recently installed any new apps? After I installed BeBuzz and Traffic, a sound byte played whenever I put my BB in standby mode. It went away when I uninstalled. Just a fluke, I guess.
Unwanted sounds from your cell phone can be a distraction! We certainly don't want to distract anyone, especially if you are at work. As SydneyK stated, may I ask what version of the blackberry OS do you have on the device? The steps will vary based on what OS you are running. In either case, to adjust the sound settings on the blackberry, you want to locate the "Profile" option and make your changes there. If you need more assistance then I would be happy to provide a more detailed layout once you share the OS that you have.
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