I experienced something that I consider rather odd:
My Tivo (Elite) suddenly started to misbehave and apparently not respond to remote commands. It then rebooted and kept rebooting. So I called Tivo tech support and they decided the unit would need to be replaced.
Luckily, I had an old Tivo HD so I plugged it in and this unit also kept rebooting. Long story short, I finally linked this to the HDMI ports on my receiver. For some reason, connecting to any receiver HDMI would cause Tivos to constantly reboot. A reboot of the receiver fixed the issue.
I again called Tivo to cancel replacement request and also asked tech support why HDMI would cause reboots. Got a bunch of nonsense answers such as "Well, HDMI is a good protocol but you need to check your power strip etc"
Does anyone know why HDMI would be causing Tivo reboots? It was certainly not affecting other HDMI connected devices (e.g., a BluRay player).