VLAN traffic some time is block by "Default deny / state violation rule", other time the traffic pass. I have an SMB share on a VLAN, for some reason some time traffic on port 445 is getting block, by default deny rule, other time traffic pass, see screenshot.
Is your NAS TRAFFIC rule not always matching?
SMB traffic is not always unicast. Did you account for this in your rules? (You blotted out the destination address, so I can't tell if that's the issue.)
I think the reason for the block was the PUSH,ACK state of the TCP packet. But the original post is over 8 months old...