I recently had my modem configuration changed from IPv6 back to IPv4 so that it works with my company’s VPN, which I now understand only accepts IPv4. My Sonos also only works with IPv4. It has been working fine for the past few weeks, until recently, when the Modem seemed to have switched back to IPv6.
I called UPC Support this morning and they indeed confirmed that the Modem had “automatically” switched back to IPv6. He changed it back to IPv4 and said I’d have to wait 24 hours until it takes effect (which is not acceptable when VPN does not function and therefore I can’t work).
--> What can be done to keep the Modem on IPv4 (i.e. prevent it from switching back to IPv6)?
I asked the UPC Support person this question but he did not know the answer. Hoping you can help!