Updated 05/25/2011: Save yourself time, money, and frustration by checking out my latest solution.
I decided to replace the Monoprice HDMI/Ethernet extenders in an attempt to resolve the signal issues with the TV in the bedroom. I replaced those adapters with a Sabrent HDMI Extension cable over Cat5/6 RJ45 Extender adapter. It is an improvement but it hasn’t removed the problem. I did finally get a steady signal light on the switch and I was able to change channels several times without any problems but later tonight it dropped the signal a couple of times.
On the bright side, this eliminates one part of the problem (and I’ll have another use for the older adapters). At this point either I need to upgrade the Cat5 to Cat6 or get a better HDMI switch.