The interesting. For several days I have a situation.
When P2P is enable, Internet on is slow, but immediately speeds up when P2P is Disabled.
My P2P settings (DNS-320) (I changed nothing for 2 years)
Maximum Download Rate (Kb/S) - 1000
Maximum Upload Rate (Kb/S) - 1000
Internet speed - 80Mb, router is OK
Is something could have changed in the NAS device?