Acoustic shock happens when loud or unannounced sounds travel through phone lines, and hit your ears.
Your ears may not know what hit them. As a result, they can suffer the auditory version of a panic attack.
We're talking some nasty stuff- ringing in the ears, inordinate sensitivity to sound, and difficulty in processing the details of sound.
In an interview with Welsh-based IP news site Ping Wales, Paul Jenkins makes a point that PC headsets used by customers of softphone providers such as Skype aren't sophisticated enough to protect against acoustic shock.
"Cheap headsets can land a company in hot water as the hearing protection is sadly lacking," says Jenkins, who is managing director of IT management solutions provider Nomadtrack. "A PC soundcard can often push four watts of sound into a headset. This has the potential to cause temporary or permanent hearing damage."
Jenkins then cites the reason for this problem: PC headsets tend to be based on hi-fi standards, not on telecommunications standards.
Ping Wales correctly points out that even though VoIP headsets can produce excellent sound quality, they are vulnerable to "unexpected tones from the local PC or the VoIP package" that can result in acoustic shock.
Keep in mind the sound doesn't have to be loud. Just unexpected.