NAT not working on 8.2.2

I’ve been using 8.2.2 without any problems in the last 3 months (all or SM are natted),
in the last week we received a new bundle of SM P10 8.2 that we upgrade to 8.2.2 as usual and from the ones we have just installed
we have already 5 SM with NAT blocking after some minutes of trafic: we can ping the LAN side, we can ping the Sm from the radio side, but from the lan side we can’t ping the firewal outside.
After rebutting the SM it starts going again
In the NAT statistics I find “Out of resource count” as you can see below

Private NAT Statistics

Packet In Count : 143708
Packet Out Count : 77792
Packet Out Toss Count : 0
Out Of Resources Count : 19951
Failed Hash Insert Count : 0
Public NAT Statistics

Packet In Count : 79262
Packet Out Count : 123747
Packet Out Toss Count : 0
Out Of Resources Count : 0
Failed Hash Insert Count : 0

Does sombody knws what is the problem ?

Ran into this at a customer site that had 2 or 3 computers infected with virus/worms/spyware. It’s chewing up all your NAT ports/resources and as a result, the older connections have to time out before new ones can be made.

You can lower the values to help with the issue. Go to Configuration > Nat, under TCP and UDP session garbage use the lowest possible values.