I have had a WRVS4400N router for the past 8-9 months. When connected to a remote VPN, The PC will intermittently drop connection to the remote VPN server. Anything running over the connection, like Remote Desktop or vSphere client or network file browsing, will be temporarily unusable while the connection is reestablished. A drop usually lasts for several seconds and varies in frequency.
A few notes:
-I can reproduce the issue with multiple PCs.
-Both wired and wireless connections are affected.
-If I use an old Linksys WRT router or directly connect to the internet modem, I do not see the issue.
-I have tried disabling UPnP, Firewall, and IPS without any success.
I have tried using wireshark, but can't identify anything specific. The traffic just seems to stop for 5-10 seconds before resuming.
Any suggestions/assistance would be appreciated.
Have you tried just the quickvpn client and seen if your still getting the disconnect?
If that is stable and the passthrough is still not working, maybe try download a fresh firmware from cisco.com then, reflash the router with the firmware then factory reset the router and manually reconfigure it with your settings and see if your seeing the same issue.
Let me know how it works out.