So I've noticed some strange behavior on my home connection (Comcast). The Mikrotik that I am using shows a constant Tx on the WAN port of around 3-5Mbps and between 200-300pps, Rx is just a few kbps. This activity appears to be strictly on the WAN port. If I disable a firewall rule that accepts input, the activity ceases - but devices behind the router lose connectivity.
Any ideas? I've got all IP services disabled except winbox, which is restricted to my local network.