Having the same problem with the UML295. Modem seems to drop connection once a day or so. It’s like Verizon kills the IP address. I wish there was a fix. I need to access my home network remotely, and I’m unable to reliably do this with this problem. I’m running a Balance 20 with firmware 5.4.7m49 build 1703.
I found a fix for this problem. I plugged a cheap electrical outlet timer into the wall, and then plugged the Balance 20 into it. Now, I have the timer cut power to the Balance 20 every 12 hours for several seconds, and then turn it back on. (Desperate times require desperate measures.)
It goes without saying that if you are trying to access the internet through a Windows machine and you are having trouble, make sure it isn’t Windows playing games with you. I often find that when using wireless network interfaces, I have to turn off the QOS, Discovery mapper, etc crapola to get a stable internet connection across the ethernet network. Else, it will often look like the 'net connection died due to a hardware glitch in the modem or a router. I often find that my Ubuntu Linux machines running nothing but a TCP/IPv4 stack have no problems whatsoever.