Hi everyone, having some issues with my Kindles and wondered if anyone had any good suggestions.

The problem is that I can connect to my Wifi router no problems with both of them, but I cannot sync with amazon. When I go "Sync & Check for Items", it seemingly checks, and then does nothing. My 'Archived Items' folder is seemingly empty. To my mind I should be able to view previously downloaded items etc from there - but there's just nothing there. I can surf to the amazon store and browse no problems. I cannot download any book samples (no error messages, I just never get them). I can transfer content onto the Kindle via USB.

Both Kindles are 3rd generation Wifi only. Both worked fine previously. One is on v3.0.2, the other is on 3.1 (I will get mine to 3.1 when I can connect!).

What I've tried:
- restarting them
- turning off encryption on the wifi
- changing from WPA2 to WPA
- ensured that the MTU on the router is 1500 (someone had exactly the same symptoms as me with an MTU issue)

What's changed?
Since they were last working (they weren't used for a couple of months) I have changed to a different Wifi router (old one broke). I think my wife's firmware must have auto-updated while the old router was still living. This "new" router seems to be the obvious suspect, but given that I can connect and surf just fine on the Kindle via Wifi, and my PC works fine via the LAN, I'm not sure what could be going wrong.

The person who had the MTU issue said they'd run wireshark across the link to work out what wasn't working. I'm not sure how he was able to snoop the traffic and pretty certain that I probably don't have the equipment to do so. Is anyone aware of how to run a packet capture on the kindle itself? Other ideas?

Things I haven't yet tried, and are leaving as a last resort:
- De-registering either Kindle, and re-registering
- Reset to factory defaults