I have a Powerhouse transceiver module TM751 and a handful of cheap ($11) lamp & light modules (mostly RadioShack) in my living room and master bedroom. I also have one wall dimmer of the more advanced, electronic type ($55 or so) in my dining room. I don't remember the make, I bought it online about 5 years ago. It has green LEDs along the side that ratchet up and down with the intensity of the dimmer setting.
Yesterday, the lights in the bedroom stopped responding to the remote, but the lights in the living room and dining room still responded. Today, the living room doesn't respond either. The only modules still responding are the transceiver itself (coffeepot in kitchen) and the dining room.
I have tested the system's modules in different rooms, with different lamps plugged into them, and with different items in the house unplugged (lots of little brick transformers for battery chargers, cordless phones, etc.). No luck, except that one long-disused appliance module I got out was briefly and intermittently effective with a lamp in the living room last night.
No new neighbor babies within a five-six house radius. Our baby monitor is 46-49mhz (we had a terrible time with interference on the 900mhz model, but nobody uses the lower band anymore). One thing to note: from the time the monitor was installed, I could here a very faint, two-burst hum with static every few seconds on the baby monitor receiver. I no longer heard that after the trouble started.
My surmise is that the transceiver unit is in the process of fading, and that only the sophisticated unit in the dining room can still receive its attenuated signals. But any other thoughts on what I could be facing would be appreciated.