Caviar Green WD20EADS-00S2B0 - Extremely Slow transfer rates? Fix? Patch? RMA?

Y have a WD20EADS but mi issue is not Reading/Writing average speed (Read 90mbs and write 70mbs aprox). My problema is in Acces Time. I have 113ms… When the NORMAL is about 13/15ms. 

Anyone know how fix this?. With a Low Level Format? Regenrating Sectors?.. Is a torture decompress or copy a big file with this acces time :S

PD: Sorry for my Bad English.Greetings from Argentina