While on the subject of network connections, my system's been like this for quite some time (even across swap of new wired router and old wired router (and matching bridge switches) a year or two ago), perhaps most noticeable since I added a wireless router to the mix a couple months back, but that probably just made it more noticeable rather than started anything. Mostly my network is wired ethernet, added the wireless when I got an ipod and that's pretty much all it's used for.
Anyway, noticed the 103 was acting like just about all my computer-related network components had during the past several weeks, in this case when I wanted to do the most recent firmware update. It was set up for a DHCP connection. In this case the 103 did not see the network when I went to check for the update. So ultimately I did what I've been doing for the past few months with my other network devices that misbehaved and gave it a manual IP address. And that was that, did the firmware update, and straw that broke the camel's back, decided to force the rest of my network devices to use manual/static IP addresses as well.
So basically stale DHCP connections have been the norm in my setup. Started a few years ago that I'm aware of, with my laser printer and a computer or two getting their DHCP addresses mixed up (something like "another device is on your network with the same address") and continued on from there, computers, printers, the wireless router, the ipod, now on to the a/v equipment. So the 103 was the last straw and I've moved everything over to manual/static addresses (that are out of range of the DHCP address pool). Now it's all good. (I think.)
I wonder if there's some DHCP conflict between the bridge and the router, don't know enough to say one way or the other. Last thing I noticed was that DHCP connections via my router seem to have a timeout of 1440 minutes (24 hours), which would explain a lot if router is reassigning addresses every 24 hours for idle equipment and the idle equipment is oblivious to their addresses being reassigned out from under them. Which does seem to be what happens. Anyway, static addresses work okay. Now I just have one DHCP device left as it doesn't seem to support manual setup (Roku 3).
If anybody knows why and what would need to be set in the router or bridge to overcome this, I'd be curious, maybe even happy, to have the mystery solved. I have gigabit Cisco router and a gigabit switch. (Prior to this had Linksys 10/100 router that slowly died over the course of several years (thought it was just my flaky ISP, which has also since been swapped out) along with a Linksys switch that stayed the course.) Setting the DHCP timeout to longer would probably just prolong the inevitable, so don't think that would suffice.