Are you certain it is the flapper?

How about the overflow tube? Is it above the water line? If it is shoved
too far down into the overflow tube it will siphon.

http://www.factsfacts.com/MyHomeRepa...let_refill.htm

http://www.factsfacts.com/MyHomeRepair/ToiletFlush.htm

"tflfb" wrote in message
...
Toilet flapper leaking down a bit toilet refils in about 30 seconds, any
fixes short of replaceing the rubber flapper.

I already flushed and cleaned the flapper and the flapper seat.

Thanks

Tom