Alfreda-
As Harold says, the crackling is due to leakage in the high voltage section 
of the monitor. Over time a considerable amount of dust collects in and 
around the high voltage circuitry. If you live near the coast or in an area 
with relatively high humidity, the moisture makes the dust slightly 
conductive which in turn creates a leakage path for the high voltage. The 
crackling you hear is the high voltage bleeding off to ground. This is not 
the type of thing a novice should attempt to repair. If you know someone who 
is comfortable working with high voltage perhaps you could get them to take 
the back off after unplugging and removing the ac line cord and carefully 
brush the dust out of the HV circuitry. Follow that with carefully running a 
vacuum around the area but don't get the vacuum too close to any components. 
If you have and air hose, you could take it outside and blow the dust out. 
Then replace the back and fire it up. It may snap and crackle a few times 
which is normal, it has special spark gap capacitors which arc over if the 
voltage gets too high. That should stop the crackling.
A shop would probably charge you approx $75 to do this. New 17" monitors are 
selling many places for as little as $49.95 so it really isn't worth taking 
it to a shop.
HTH
Good Luck
John Dinges 

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