I've had devices do that before and usually is was caused by them losing power at some point. My reasoning was that when you plug these particular devices in the first time they need to use the physical button to turn on because they are completely off initially. After the initial power on, they never turn completely off, but instead enter a low power state from which they can still detect the IR signal from your remote. However, If you unplug them or they lose power for any reason, they again need to be turned on using the physical button because they are completely off again. Did you perhaps suffer from some flaky electrical service before these devices began acting up? Are they both plugged into the same power strip? If so, I would probably start there. If electrical service is inconsistent in your area you might even need a UPS.