<unk>  is the symptoms a person may experience after hearing an unexpected, loud sound via a telephone. The loud sound, called an<unk>  Incident, can be caused by feedback oscillation, fax tones, or signalling tones.
Telemarketers and call centre employees are thought to be most at risk.
Acoustic shock
Electric shock
Spinal shock
Cardioplegia
Obstructive shock
Neurogenic shock
Distributive shock
Blast injury