Networker backup problem after update?

hello,

i've problem in backup using networker emc from v 8.0.2 to 8.2.0.1 i found my configuration normally and can connect to it but when i run an incremental backup it takes huge data and it's not normal or not like the previous version.  for example i run backup on my fileshare server when using V 8.0.2 the size of incremental backup between 15 G to 25G daily. but after update to 8.2.0.1 i found the size of incremental backup reach to (first day after update) 5000 GB, second and third day were  the same size. so how can i fix this issue and is this normal????

the networker server attached with data domain and works normal, also when i check the duplication on data domain is within 21X 

so i just need to check if this is normal with the new version of networker that i updated or has new structure in read/write data or just add the new data wit the old one????