When you mentioned that it only happens while watching TV, my first thought was possibly some kind of seizure activity. Have you had an EEG done?
Michelle
Just a suggestion here,
Could be CAPD - Central auditory processing disorder.
CAPD can occur in a variety of circumstances: if people have brain lesions; if someone has suffered a traumatic brain injury; in those with a history of chronic ear infections; in older adults, as a result of neurologic changes due to aging; or in children with learning disabilities such as dyslexia, developmental language disorder, or attention deficit disorder.
CAPD is tricky for even a specialist to diagnose because people with CAPD can usually pass ordinary hearing tests, where an audiometer emits assorted tones of varying frequency and intensity the disorder frequently goes undiagnosed. "Often it's misdiagnosed as ADHD," and......
http://dartmed.dartmouth.edu/summer00/html/scrambled_sounds.shtml