It is probably degaussing when you start it. this I synonymous with
demagnetizing. My step dad's 19" Dell (Sony) flat screen comes on with a
very loud "twung". I doubt if it is anything to be concerned with. Some
monitors have Degaussing buttons that accomplish the same thing, yours
appears to be automatic at start up.
Brad Loomis
Los Angeles, CA

My monitor has started with that noise since I bought it in 12/97.  It still
is in use, and works just fine.
>when I switch my monitor on, it starts with a " twung  or Dung noise",
>little louder than the normal starting indication.
>  Can somebody please tell me what it is .Is it a signal for a future
trouble ?

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