People in the house complain about no Internet and I can confirm that I can't ping anything on my network when it happens but rebooting the TV makes it go away. I initially thought it was the switch, but replacing it didn't help. The only thing that reliably works is rebooting the TV.
I like the picture, but between this networking issue and what feels like an incredibly underpowered UI, I wish I had bought another TV.
Have you tried replacing the ethernet cable?