Wireless issue regarding incoming connection attempts

I am seeing an odd issue with my wireless and I was hoping someone could help me out. I put OpenWRT on a Linksys WRT 1900 ACS awhile back and the kind people here helped me hammer out a lot of my issues.

I currently have three Windows 7 machines hooked up to the router, two hardwired and one via wireless. The wireless is a pretty standard configuration. The issue only happens with the wireless. When I first boot up I see incoming connections (which my firewall blocks), from both the IP address of the router, and the computer IP address. When the AV checks for updates, I then get 'reciprocal' incoming attempts from the AV IP address. If I surf, then whatever website I go to shows incoming connection attempts from that IP address. This happens with any program I use. All incoming attempts are via svchost.exe. The port is always something odd, like 49,162, 50,245, etc.

So, I ran a test and hard wired this comp, and just like the other two, none of this happened. I took the old router and set that back up and connected via wireless on the problem comp, and no issue. Back to the OpenWRT, and the issue was right back.

I simply don't have the networking or other skills to understand this, or 'fix' it. Note that everything works fine with all these incoming connection attempts blocked, but I know it means something is not set up right, and I'd like to resolve it. Any advice here would be greatly appreciated.

My bad on this one. I reran my test on the old wireless router again (twice) and it appears the issue also exists with that one. I have no idea why it seemed okay on the first test with that. So, it seems this is a Windows issue. I will try to hunt up some kind of Windows forum and ask them for help. Sorry to waste everyone's time in here. If I ever do solve this and anyone wants to know what it was just for the sake of the knowledge, post a note in here and I'll reply back.