We used to have a lot of trouble desyncing in Nadox. We found adjusting our filters (along with turning down graphic settings) worked to cure this. Check out this post below
viewtopic.php?f=9&t=8313&p=48574#p48574Since doing this i went from always desyncing on fights like Vist to only desyncing maybe 5 times in total since then, usually in HoH when its packed.